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    <loc xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_EntityIncorporationStateCountryCode" xlink:label="loc_dei_EntityIncorporationStateCountryCode" xlink:type="locator"/>
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    <loc xlink:href="https://xbrl.sec.gov/dei/2020/dei-2020-01-31.xsd#dei_AmendmentDescription" xlink:label="loc_dei_AmendmentDescription" xlink:type="locator"/>
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    <label xlink:label="lab_us-gaap_StatementOfFinancialPositionAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Financial Position [Abstract]</label>
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    <label xlink:label="lab_us-gaap_StatementTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementTable" xlink:to="lab_us-gaap_StatementTable" xlink:type="arc"/>
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    <label xlink:label="lab_us-gaap_StatementLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement [Line Items]</label>
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    <label xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">LIABILITIES AND SHAREHOLDER'S EQUITY</label>
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    <label xlink:label="lab_us-gaap_LiabilitiesCurrentAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities, Current [Abstract]</label>
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    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesCurrentAbstract" xlink:to="lab_us-gaap_LiabilitiesCurrentAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AccruedLiabilitiesCurrent" xlink:label="loc_us-gaap_AccruedLiabilitiesCurrent" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued Liabilities, Current</label>
    <label xlink:label="lab_us-gaap_AccruedLiabilitiesCurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued offering costs</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccruedLiabilitiesCurrent" xlink:to="lab_us-gaap_AccruedLiabilitiesCurrent" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_AccruedExpensesCurrent" xlink:label="loc_atac_AccruedExpensesCurrent" xlink:type="locator"/>
    <label xlink:label="lab_atac_AccruedExpensesCurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accrued expenses Current</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="loc_us-gaap_LiabilitiesCurrent" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_LiabilitiesCurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liabilities, Current</label>
    <label xlink:label="lab_us-gaap_LiabilitiesCurrent" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total Current Liabilities</label>
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    <label xlink:label="lab_us-gaap_Liabilities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total Liabilities</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Liabilities" xlink:to="lab_us-gaap_Liabilities" xlink:type="arc"/>
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    <label xlink:label="lab_us-gaap_StockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Attributable to Parent [Abstract]</label>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockValue" xlink:label="loc_us-gaap_CommonStockValue" xlink:type="locator"/>
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    <label xlink:label="lab_us-gaap_AdditionalPaidInCapital" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additional paid-in capital</label>
    <label xlink:label="lab_us-gaap_AdditionalPaidInCapital" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Additional Paid-in Capital</label>
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    <label xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total Shareholders' Equity</label>
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    <label xlink:label="lab_us-gaap_StockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shareholders' Equity</label>
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    <label xlink:label="lab_us-gaap_LiabilitiesAndStockholdersEquity" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="lab_us-gaap_LiabilitiesAndStockholdersEquity" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_DeferredUnderwritingFeePayableNoncurrent" xlink:label="loc_atac_DeferredUnderwritingFeePayableNoncurrent" xlink:type="locator"/>
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    <label xlink:label="lab_atac_DeferredUnderwritingFeePayableNoncurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred underwriting fee payable</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DeferredUnderwritingFeePayableNoncurrent" xlink:to="lab_atac_DeferredUnderwritingFeePayableNoncurrent" xlink:type="arc"/>
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    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TemporaryEquityCarryingAmountAttributableToParent" xlink:label="loc_us-gaap_TemporaryEquityCarryingAmountAttributableToParent" xlink:type="locator"/>
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    <label xlink:label="lab_us-gaap_WarrantsAndRightsOutstanding" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Warrant liability</label>
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    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WarrantsAndRightsOutstanding" xlink:to="lab_us-gaap_WarrantsAndRightsOutstanding" xlink:type="arc"/>
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    <label xlink:label="lab_us-gaap_AssetsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets [Abstract]</label>
    <label xlink:label="lab_us-gaap_AssetsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">ASSETS</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsAbstract" xlink:to="lab_us-gaap_AssetsAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_Assets" xlink:label="loc_us-gaap_Assets" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_Assets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets</label>
    <label xlink:label="lab_us-gaap_Assets" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">TOTAL ASSETS</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Assets" xlink:to="lab_us-gaap_Assets" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AssetsCurrentAbstract" xlink:label="loc_us-gaap_AssetsCurrentAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AssetsCurrentAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Current [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsCurrentAbstract" xlink:to="lab_us-gaap_AssetsCurrentAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_Cash" xlink:label="loc_us-gaap_Cash" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_Cash" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash</label>
    <label xlink:label="lab_us-gaap_Cash" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_Cash" xlink:to="lab_us-gaap_Cash" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PrepaidExpenseCurrent" xlink:label="loc_us-gaap_PrepaidExpenseCurrent" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_PrepaidExpenseCurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Prepaid Expense, Current</label>
    <label xlink:label="lab_us-gaap_PrepaidExpenseCurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Prepaid expenses</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrepaidExpenseCurrent" xlink:to="lab_us-gaap_PrepaidExpenseCurrent" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="loc_us-gaap_AssetsCurrent" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AssetsCurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Current</label>
    <label xlink:label="lab_us-gaap_AssetsCurrent" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total Current Assets</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsCurrent" xlink:to="lab_us-gaap_AssetsCurrent" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AssetsHeldInTrustNoncurrent" xlink:label="loc_us-gaap_AssetsHeldInTrustNoncurrent" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AssetsHeldInTrustNoncurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets Held-in-trust, Noncurrent</label>
    <label xlink:label="lab_us-gaap_AssetsHeldInTrustNoncurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash and marketable securities held in Trust Account</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsHeldInTrustNoncurrent" xlink:to="lab_us-gaap_AssetsHeldInTrustNoncurrent" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:label="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:to="lab_us-gaap_RelatedPartyTransactionsByRelatedPartyAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RelatedPartyDomain" xlink:label="loc_us-gaap_RelatedPartyDomain" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RelatedPartyDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party [Domain]</label>
    <label xlink:label="lab_us-gaap_RelatedPartyDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyDomain" xlink:to="lab_us-gaap_RelatedPartyDomain" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsequentEventTypeAxis" xlink:label="loc_us-gaap_SubsequentEventTypeAxis" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SubsequentEventTypeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Event Type [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTypeAxis" xlink:to="lab_us-gaap_SubsequentEventTypeAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsequentEventTypeDomain" xlink:label="loc_us-gaap_SubsequentEventTypeDomain" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SubsequentEventTypeDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Event Type [Domain]</label>
    <label xlink:label="lab_us-gaap_SubsequentEventTypeDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Subsequent Event Type [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventTypeDomain" xlink:to="lab_us-gaap_SubsequentEventTypeDomain" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PreferredStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_PreferredStockParOrStatedValuePerShare" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Par or Stated Value Per Share</label>
    <label xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, par value</label>
    <label xlink:label="lab_us-gaap_PreferredStockParOrStatedValuePerShare" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Preferred shares, par value</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockParOrStatedValuePerShare" xlink:to="lab_us-gaap_PreferredStockParOrStatedValuePerShare" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_PreferredStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Shares Authorized</label>
    <label xlink:label="lab_us-gaap_PreferredStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, shares authorized</label>
    <label xlink:label="lab_us-gaap_PreferredStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Preferred shares, shares authorized</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesAuthorized" xlink:to="lab_us-gaap_PreferredStockSharesAuthorized" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PreferredStockSharesIssued" xlink:label="loc_us-gaap_PreferredStockSharesIssued" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_PreferredStockSharesIssued" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Shares Issued</label>
    <label xlink:label="lab_us-gaap_PreferredStockSharesIssued" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, shares issued</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesIssued" xlink:to="lab_us-gaap_PreferredStockSharesIssued" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="loc_us-gaap_PreferredStockSharesOutstanding" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_PreferredStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Preferred Stock, Shares Outstanding</label>
    <label xlink:label="lab_us-gaap_PreferredStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Preferred stock, shares outstanding</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PreferredStockSharesOutstanding" xlink:to="lab_us-gaap_PreferredStockSharesOutstanding" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockParOrStatedValuePerShare" xlink:label="loc_us-gaap_CommonStockParOrStatedValuePerShare" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Par or Stated Value Per Share</label>
    <label xlink:label="lab_us-gaap_CommonStockParOrStatedValuePerShare" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, par value</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockParOrStatedValuePerShare" xlink:to="lab_us-gaap_CommonStockParOrStatedValuePerShare" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="loc_us-gaap_CommonStockSharesAuthorized" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares Authorized</label>
    <label xlink:label="lab_us-gaap_CommonStockSharesAuthorized" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares authorized</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesAuthorized" xlink:to="lab_us-gaap_CommonStockSharesAuthorized" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockSharesIssued" xlink:label="loc_us-gaap_CommonStockSharesIssued" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CommonStockSharesIssued" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares, Issued</label>
    <label xlink:label="lab_us-gaap_CommonStockSharesIssued" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares issued</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesIssued" xlink:to="lab_us-gaap_CommonStockSharesIssued" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="loc_us-gaap_CommonStockSharesOutstanding" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Shares, Outstanding</label>
    <label xlink:label="lab_us-gaap_CommonStockSharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares outstanding</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockSharesOutstanding" xlink:to="lab_us-gaap_CommonStockSharesOutstanding" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TemporaryEquitySharesOutstanding" xlink:label="loc_us-gaap_TemporaryEquitySharesOutstanding" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_TemporaryEquitySharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Temporary Equity, Shares Outstanding</label>
    <label xlink:label="lab_us-gaap_TemporaryEquitySharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Temporary Equity Shares Outstanding</label>
    <label xlink:label="lab_us-gaap_TemporaryEquitySharesOutstanding" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Possible redemption</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TemporaryEquitySharesOutstanding" xlink:to="lab_us-gaap_TemporaryEquitySharesOutstanding" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TemporaryEquityParOrStatedValuePerShare" xlink:label="loc_us-gaap_TemporaryEquityParOrStatedValuePerShare" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_TemporaryEquityParOrStatedValuePerShare" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Temporary Equity, Par or Stated Value Per Share</label>
    <label xlink:label="lab_us-gaap_TemporaryEquityParOrStatedValuePerShare" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Temporary Equity Par Value Per Share</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TemporaryEquityParOrStatedValuePerShare" xlink:to="lab_us-gaap_TemporaryEquityParOrStatedValuePerShare" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsidiarySaleOfStockAxis" xlink:label="loc_us-gaap_SubsidiarySaleOfStockAxis" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SubsidiarySaleOfStockAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsidiarySaleOfStockAxis" xlink:to="lab_us-gaap_SubsidiarySaleOfStockAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SaleOfStockNameOfTransactionDomain" xlink:label="loc_us-gaap_SaleOfStockNameOfTransactionDomain" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SaleOfStockNameOfTransactionDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock [Domain]</label>
    <label xlink:label="lab_us-gaap_SaleOfStockNameOfTransactionDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sale of Stock [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockNameOfTransactionDomain" xlink:to="lab_us-gaap_SaleOfStockNameOfTransactionDomain" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeStatementAbstract" xlink:label="loc_us-gaap_IncomeStatementAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_IncomeStatementAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Statement [Abstract]</label>
    <label xlink:label="lab_us-gaap_IncomeStatementAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">STATEMENT OF OPERATIONS</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeStatementAbstract" xlink:to="lab_us-gaap_IncomeStatementAbstract" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_FormationAndOperatingCosts" xlink:label="loc_atac_FormationAndOperatingCosts" xlink:type="locator"/>
    <label xlink:label="lab_atac_FormationAndOperatingCosts" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Formation And Operating Costs</label>
    <label xlink:label="lab_atac_FormationAndOperatingCosts" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Formation and operational costs</label>
    <label xlink:label="lab_atac_FormationAndOperatingCosts" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Payment of formation costs in exchange for issuance of Class B ordinary shares</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_FormationAndOperatingCosts" xlink:to="lab_atac_FormationAndOperatingCosts" xlink:type="arc"/>
    <label xlink:label="lab_atac_FormationAndOperatingCosts" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">"Amount of formation and operating costs incurred during the period. "</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:label="loc_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Number of Shares Outstanding, Basic and Diluted</label>
    <label xlink:label="lab_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted average shares outstanding, basic and diluted</label>
    <label xlink:label="lab_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Redeemable Class&#xA0;A Ordinary Shares, Basic and Diluted</label>
    <label xlink:label="lab_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:type="resource" xml:lang="en-US">Non-Redeemable Class&#xA0;B Ordinary Shares, Basic and Diluted</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:to="lab_us-gaap_WeightedAverageNumberOfShareOutstandingBasicAndDiluted" xlink:type="arc"/>
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    <label xlink:label="lab_us-gaap_EarningsPerShareBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Basic and Diluted</label>
    <label xlink:label="lab_us-gaap_EarningsPerShareBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basic and diluted net loss per ordinary shares</label>
    <label xlink:label="lab_us-gaap_EarningsPerShareBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/presentationGuidance" xlink:type="resource" xml:lang="en-US">Basic and diluted net loss per share, Class B</label>
    <label xlink:label="lab_us-gaap_EarningsPerShareBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/definitionGuidance" xlink:type="resource" xml:lang="en-US">Earnings/Basic and Diluted Redeemable Class&#xA0;A Ordinary Shares</label>
    <label xlink:label="lab_us-gaap_EarningsPerShareBasicAndDiluted" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Loss/Basic and Diluted Non-Redeemable Class&#xA0;B Ordinary Shares</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareBasicAndDiluted" xlink:to="lab_us-gaap_EarningsPerShareBasicAndDiluted" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_OperatingIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Operating Income (Loss)</label>
    <label xlink:label="lab_us-gaap_OperatingIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Loss from operations</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingIncomeLoss" xlink:to="lab_us-gaap_OperatingIncomeLoss" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NonoperatingIncomeExpenseAbstract" xlink:label="loc_us-gaap_NonoperatingIncomeExpenseAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NonoperatingIncomeExpenseAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Nonoperating Income (Expense) [Abstract]</label>
    <label xlink:label="lab_us-gaap_NonoperatingIncomeExpenseAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other (expense) income:</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NonoperatingIncomeExpenseAbstract" xlink:to="lab_us-gaap_NonoperatingIncomeExpenseAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetIncomeLoss" xlink:label="loc_us-gaap_NetIncomeLoss" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss) Attributable to Parent</label>
    <label xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net loss</label>
    <label xlink:label="lab_us-gaap_NetIncomeLoss" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net loss</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetIncomeLoss" xlink:to="lab_us-gaap_NetIncomeLoss" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_InvestmentIncomeInterest" xlink:label="loc_us-gaap_InvestmentIncomeInterest" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_InvestmentIncomeInterest" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Investment Income, Interest</label>
    <label xlink:label="lab_us-gaap_InvestmentIncomeInterest" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Interest earned on marketable securities held in Trust Account</label>
    <label xlink:label="lab_us-gaap_InvestmentIncomeInterest" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Interest earned on marketable securities held in Trust Account</label>
    <label xlink:label="lab_us-gaap_InvestmentIncomeInterest" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest Income</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_InvestmentIncomeInterest" xlink:to="lab_us-gaap_InvestmentIncomeInterest" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueAdjustmentOfWarrants" xlink:label="loc_us-gaap_FairValueAdjustmentOfWarrants" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FairValueAdjustmentOfWarrants" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Adjustment of Warrants</label>
    <label xlink:label="lab_us-gaap_FairValueAdjustmentOfWarrants" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Change in fair value of warrants</label>
    <label xlink:label="lab_us-gaap_FairValueAdjustmentOfWarrants" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Change in fair value of warrant liability</label>
    <label xlink:label="lab_us-gaap_FairValueAdjustmentOfWarrants" xlink:role="http://www.xbrl.org/2009/role/negatedTerseLabel" xlink:type="resource" xml:lang="en-US">Change in fair value of warrant liability</label>
    <label xlink:label="lab_us-gaap_FairValueAdjustmentOfWarrants" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Change in valuation inputs or other assumptions</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAdjustmentOfWarrants" xlink:to="lab_us-gaap_FairValueAdjustmentOfWarrants" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementOfStockholdersEquityAbstract" xlink:label="loc_us-gaap_StatementOfStockholdersEquityAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_StatementOfStockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Stockholders' Equity [Abstract]</label>
    <label xlink:label="lab_us-gaap_StatementOfStockholdersEquityAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">STATEMENT OF CHANGES IN SHAREHOLDERS' EQUITY</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfStockholdersEquityAbstract" xlink:to="lab_us-gaap_StatementOfStockholdersEquityAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Stockholders' Equity [Roll Forward]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:to="lab_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Value, New Issues</label>
    <label xlink:label="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Issuance of Class B common stock to Sponsors</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:to="lab_us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Issued During Period, Shares, New Issues</label>
    <label xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Issuance of Class B common stock to Sponsors (in shares)</label>
    <label xlink:label="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Sale of 27,500,000 Units, net of underwriting discounts and offering costs</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:to="lab_us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SharesIssued" xlink:label="loc_us-gaap_SharesIssued" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SharesIssued" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Shares, Issued</label>
    <label xlink:label="lab_us-gaap_SharesIssued" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Balance at the end (in shares)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharesIssued" xlink:to="lab_us-gaap_SharesIssued" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Adjustments to Additional Paid in Capital, Warrant Issued</label>
    <label xlink:label="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sale of 5,000,000 Private Placement Warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:to="lab_us-gaap_AdjustmentsToAdditionalPaidInCapitalWarrantIssued" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_StockForfeitedDuringPeriodValue" xlink:label="loc_atac_StockForfeitedDuringPeriodValue" xlink:type="locator"/>
    <label xlink:label="lab_atac_StockForfeitedDuringPeriodValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Forfeited During Period Value</label>
    <label xlink:label="lab_atac_StockForfeitedDuringPeriodValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Forfeiture of Founder Shares</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_StockForfeitedDuringPeriodValue" xlink:to="lab_atac_StockForfeitedDuringPeriodValue" xlink:type="arc"/>
    <label xlink:label="lab_atac_StockForfeitedDuringPeriodValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock forfeited during period, value.</label>
    <loc xlink:href="atac-20201231.xsd#atac_StockForfeitedDuringPeriodShares" xlink:label="loc_atac_StockForfeitedDuringPeriodShares" xlink:type="locator"/>
    <label xlink:label="lab_atac_StockForfeitedDuringPeriodShares" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Forfeited During Period Shares</label>
    <label xlink:label="lab_atac_StockForfeitedDuringPeriodShares" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Forfeiture of Founder Shares (in shares)</label>
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    <label xlink:label="lab_atac_StockForfeitedDuringPeriodShares" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock forfeited during period, shares.</label>
    <loc xlink:href="atac-20201231.xsd#atac_StockTransferredToTemporaryEquityValue" xlink:label="loc_atac_StockTransferredToTemporaryEquityValue" xlink:type="locator"/>
    <label xlink:label="lab_atac_StockTransferredToTemporaryEquityValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Transferred To Temporary Equity Value</label>
    <label xlink:label="lab_atac_StockTransferredToTemporaryEquityValue" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class A ordinary shares subject to possible redemption</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_StockTransferredToTemporaryEquityValue" xlink:to="lab_atac_StockTransferredToTemporaryEquityValue" xlink:type="arc"/>
    <label xlink:label="lab_atac_StockTransferredToTemporaryEquityValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock transferred to temporary equity value.</label>
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    <label xlink:label="lab_atac_StockTransferredToTemporaryEquityShares" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stock Transferred To Temporary Equity Shares</label>
    <label xlink:label="lab_atac_StockTransferredToTemporaryEquityShares" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Class A ordinary shares subject to possible redemption (in shares)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_StockTransferredToTemporaryEquityShares" xlink:to="lab_atac_StockTransferredToTemporaryEquityShares" xlink:type="arc"/>
    <label xlink:label="lab_atac_StockTransferredToTemporaryEquityShares" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Stock transferred to temporary equity shares.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ClassOfWarrantsOrRightsWarrantsIssuedDuringThePeriodValue" xlink:label="loc_atac_ClassOfWarrantsOrRightsWarrantsIssuedDuringThePeriodValue" xlink:type="locator"/>
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    <label xlink:label="lab_atac_ClassOfWarrantsOrRightsWarrantsIssuedDuringThePeriodValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Class of warrants or rights warrants issued during the period value.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="loc_us-gaap_StatementEquityComponentsAxis" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_StatementEquityComponentsAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Components [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementEquityComponentsAxis" xlink:to="lab_us-gaap_StatementEquityComponentsAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain" xlink:label="loc_us-gaap_EquityComponentDomain" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_EquityComponentDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Equity Component [Domain]</label>
    <label xlink:label="lab_us-gaap_EquityComponentDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Equity Component [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EquityComponentDomain" xlink:to="lab_us-gaap_EquityComponentDomain" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Additional Paid-in Capital [Member]</label>
    <label xlink:label="lab_us-gaap_AdditionalPaidInCapitalMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Additional Paid-in Capital</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdditionalPaidInCapitalMember" xlink:to="lab_us-gaap_AdditionalPaidInCapitalMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="loc_us-gaap_RetainedEarningsMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RetainedEarningsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Retained Earnings [Member]</label>
    <label xlink:label="lab_us-gaap_RetainedEarningsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accumulated Deficit</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RetainedEarningsMember" xlink:to="lab_us-gaap_RetainedEarningsMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockMember" xlink:label="loc_us-gaap_CommonStockMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CommonStockMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock [Member]</label>
    <label xlink:label="lab_us-gaap_CommonStockMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common Stock</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockMember" xlink:to="lab_us-gaap_CommonStockMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BeneficialOwnerMember" xlink:label="loc_us-gaap_BeneficialOwnerMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_BeneficialOwnerMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Beneficial Owner [Member]</label>
    <label xlink:label="lab_us-gaap_BeneficialOwnerMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sponsor</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BeneficialOwnerMember" xlink:to="lab_us-gaap_BeneficialOwnerMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:label="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right, Number of Securities Called by Warrants or Rights</label>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Private Placement Warrants</label>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of warrants issued</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:to="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByWarrantsOrRights" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PrivatePlacementMember" xlink:label="loc_us-gaap_PrivatePlacementMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_PrivatePlacementMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Private Placement [Member]</label>
    <label xlink:label="lab_us-gaap_PrivatePlacementMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Private Placement</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PrivatePlacementMember" xlink:to="lab_us-gaap_PrivatePlacementMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="loc_us-gaap_StatementOfCashFlowsAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statement of Cash Flows [Abstract]</label>
    <label xlink:label="lab_us-gaap_StatementOfCashFlowsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">STATEMENT OF CASH FLOWS</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StatementOfCashFlowsAbstract" xlink:to="lab_us-gaap_StatementOfCashFlowsAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivitiesAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProfitLoss" xlink:label="loc_us-gaap_ProfitLoss" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ProfitLoss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Income (Loss), Including Portion Attributable to Noncontrolling Interest</label>
    <label xlink:label="lab_us-gaap_ProfitLoss" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Net loss</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProfitLoss" xlink:to="lab_us-gaap_ProfitLoss" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract]</label>
    <label xlink:label="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Adjustments to reconcile net loss to net cash used in operating activities:</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="lab_us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Operating Activities</label>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash used in operating activities</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInOperatingActivities" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Operating Capital [Abstract]</label>
    <label xlink:label="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Changes in operating assets and liabilities:</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:to="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:label="loc_us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Prepaid Expense</label>
    <label xlink:label="lab_us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Prepaid expenses</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:to="lab_us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Accrued Liabilities</label>
    <label xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Accrued expenses</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:to="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents</label>
    <label xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:type="resource" xml:lang="en-US">Cash - Beginning</label>
    <label xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:type="resource" xml:lang="en-US">Cash - Ending</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:label="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect</label>
    <label xlink:label="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net Change in Cash</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:to="lab_us-gaap_CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:label="loc_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Noncash Investing and Financing Items [Abstract]</label>
    <label xlink:label="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Non-cash investing and financing activities:</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:to="lab_us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_DeferredOfferingCostsPaidBySponsorInExchangeForIssuanceOfClassBOrdinaryShares" xlink:label="loc_atac_DeferredOfferingCostsPaidBySponsorInExchangeForIssuanceOfClassBOrdinaryShares" xlink:type="locator"/>
    <label xlink:label="lab_atac_DeferredOfferingCostsPaidBySponsorInExchangeForIssuanceOfClassBOrdinaryShares" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred offering costs Paid by Sponsor in exchange for issuance of Class B ordinary shares</label>
    <label xlink:label="lab_atac_DeferredOfferingCostsPaidBySponsorInExchangeForIssuanceOfClassBOrdinaryShares" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Offering costs paid directly by Sponsor from proceeds of issuance of Class B ordinary shares</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DeferredOfferingCostsPaidBySponsorInExchangeForIssuanceOfClassBOrdinaryShares" xlink:to="lab_atac_DeferredOfferingCostsPaidBySponsorInExchangeForIssuanceOfClassBOrdinaryShares" xlink:type="arc"/>
    <label xlink:label="lab_atac_DeferredOfferingCostsPaidBySponsorInExchangeForIssuanceOfClassBOrdinaryShares" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The amount of deferred offering costs paid through sponsor by exchange of ordinary shares.</label>
    <loc xlink:href="atac-20201231.xsd#atac_DeferredOfferingCostsIncludedInAccruedOfferingCostsIncurredDuringNonCashOrPartialNonCashTransaction" xlink:label="loc_atac_DeferredOfferingCostsIncludedInAccruedOfferingCostsIncurredDuringNonCashOrPartialNonCashTransaction" xlink:type="locator"/>
    <label xlink:label="lab_atac_DeferredOfferingCostsIncludedInAccruedOfferingCostsIncurredDuringNonCashOrPartialNonCashTransaction" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Offering Costs Included In Accrued Offering Costs Incurred During Non Cash Or Partial Non Cash Transaction</label>
    <label xlink:label="lab_atac_DeferredOfferingCostsIncludedInAccruedOfferingCostsIncurredDuringNonCashOrPartialNonCashTransaction" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Offering costs included in accrued offering costs</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DeferredOfferingCostsIncludedInAccruedOfferingCostsIncurredDuringNonCashOrPartialNonCashTransaction" xlink:to="lab_atac_DeferredOfferingCostsIncludedInAccruedOfferingCostsIncurredDuringNonCashOrPartialNonCashTransaction" xlink:type="arc"/>
    <label xlink:label="lab_atac_DeferredOfferingCostsIncludedInAccruedOfferingCostsIncurredDuringNonCashOrPartialNonCashTransaction" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">"The amount of offering costs included in accrued offering costs that were incurred during a non-cash or partial non-cash transaction. "</label>
    <loc xlink:href="atac-20201231.xsd#atac_DeferredOfferingCostsPaidThroughRelatedPartyDebt" xlink:label="loc_atac_DeferredOfferingCostsPaidThroughRelatedPartyDebt" xlink:type="locator"/>
    <label xlink:label="lab_atac_DeferredOfferingCostsPaidThroughRelatedPartyDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Offering Costs Paid Through Related Party Debt</label>
    <label xlink:label="lab_atac_DeferredOfferingCostsPaidThroughRelatedPartyDebt" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Offering costs paid through promissory note &#x2013; related party</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DeferredOfferingCostsPaidThroughRelatedPartyDebt" xlink:to="lab_atac_DeferredOfferingCostsPaidThroughRelatedPartyDebt" xlink:type="arc"/>
    <label xlink:label="lab_atac_DeferredOfferingCostsPaidThroughRelatedPartyDebt" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The amount of deferred offering costs paid through promissory note of related party.</label>
    <loc xlink:href="atac-20201231.xsd#atac_InitialClassificationOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:label="loc_atac_InitialClassificationOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:type="locator"/>
    <label xlink:label="lab_atac_InitialClassificationOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Initial classification of ClassA ordinary shares subject to possible redemption</label>
    <label xlink:label="lab_atac_InitialClassificationOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Initial classification of Class A ordinary shares subject to possible redemption</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_InitialClassificationOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:to="lab_atac_InitialClassificationOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:type="arc"/>
    <label xlink:label="lab_atac_InitialClassificationOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Initial classification of Class&#xA0;A ordinary shares subject to possible redemption.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ChangeInValueOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:label="loc_atac_ChangeInValueOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:type="locator"/>
    <label xlink:label="lab_atac_ChangeInValueOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Change in value of ClassA ordinary shares subject to possible redemption</label>
    <label xlink:label="lab_atac_ChangeInValueOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Change in value of Class A ordinary shares subject to possible redemption</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ChangeInValueOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:to="lab_atac_ChangeInValueOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:type="arc"/>
    <label xlink:label="lab_atac_ChangeInValueOfClassaOrdinarySharesSubjectToPossibleRedemption" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Change in value of Class&#xA0;A ordinary shares subject to possible redemption.</label>
    <loc xlink:href="atac-20201231.xsd#atac_DeferredUnderwritingFeePayable" xlink:label="loc_atac_DeferredUnderwritingFeePayable" xlink:type="locator"/>
    <label xlink:label="lab_atac_DeferredUnderwritingFeePayable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred underwriting fee payable</label>
    <label xlink:label="lab_atac_DeferredUnderwritingFeePayable" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred underwriting fee payable</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DeferredUnderwritingFeePayable" xlink:to="lab_atac_DeferredUnderwritingFeePayable" xlink:type="arc"/>
    <label xlink:label="lab_atac_DeferredUnderwritingFeePayable" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Deferred underwriting fee payable.</label>
    <loc xlink:href="atac-20201231.xsd#atac_InitialClassificationOfWarrantLiability" xlink:label="loc_atac_InitialClassificationOfWarrantLiability" xlink:type="locator"/>
    <label xlink:label="lab_atac_InitialClassificationOfWarrantLiability" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Initial Classification Of Warrant Liability</label>
    <label xlink:label="lab_atac_InitialClassificationOfWarrantLiability" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Initial classification of warrant liability</label>
    <label xlink:label="lab_atac_InitialClassificationOfWarrantLiability" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Initial measurement on October 27, 2020</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_InitialClassificationOfWarrantLiability" xlink:to="lab_atac_InitialClassificationOfWarrantLiability" xlink:type="arc"/>
    <label xlink:label="lab_atac_InitialClassificationOfWarrantLiability" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Initial classification of warrant liability.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities [Abstract]</label>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash Flows from Financing Activities:</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivitiesAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromRelatedPartyDebt" xlink:label="loc_us-gaap_ProceedsFromRelatedPartyDebt" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ProceedsFromRelatedPartyDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Related Party Debt</label>
    <label xlink:label="lab_us-gaap_ProceedsFromRelatedPartyDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from promissory note &#x2013; related party</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromRelatedPartyDebt" xlink:to="lab_us-gaap_ProceedsFromRelatedPartyDebt" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RepaymentsOfRelatedPartyDebt" xlink:label="loc_us-gaap_RepaymentsOfRelatedPartyDebt" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RepaymentsOfRelatedPartyDebt" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Repayments of Related Party Debt</label>
    <label xlink:label="lab_us-gaap_RepaymentsOfRelatedPartyDebt" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Payments of offering costs</label>
    <label xlink:label="lab_us-gaap_RepaymentsOfRelatedPartyDebt" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Repayment of promissory note - related party</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RepaymentsOfRelatedPartyDebt" xlink:to="lab_us-gaap_RepaymentsOfRelatedPartyDebt" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PaymentsOfStockIssuanceCosts" xlink:label="loc_us-gaap_PaymentsOfStockIssuanceCosts" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_PaymentsOfStockIssuanceCosts" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments of Stock Issuance Costs</label>
    <label xlink:label="lab_us-gaap_PaymentsOfStockIssuanceCosts" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Payments of offering costs</label>
    <label xlink:label="lab_us-gaap_PaymentsOfStockIssuanceCosts" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Offering costs paid</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsOfStockIssuanceCosts" xlink:to="lab_us-gaap_PaymentsOfStockIssuanceCosts" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Financing Activities</label>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash provided by financing activities</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInFinancingActivities" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Issuance of Common Stock</label>
    <label xlink:label="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from sale of Units, net of underwriting discounts paid</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfCommonStock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Issuance of Private Placement</label>
    <label xlink:label="lab_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from sale of Private Placement Warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfPrivatePlacement" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities [Abstract]</label>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash Flows from Investing Activities:</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivitiesAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:label="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Cash Provided by (Used in) Investing Activities</label>
    <label xlink:label="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Net cash used in investing activities</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:to="lab_us-gaap_NetCashProvidedByUsedInInvestingActivities" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PaymentsToAcquireTrustPreferredInvestments" xlink:label="loc_us-gaap_PaymentsToAcquireTrustPreferredInvestments" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_PaymentsToAcquireTrustPreferredInvestments" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Payments to Acquire Trust Preferred Investments</label>
    <label xlink:label="lab_us-gaap_PaymentsToAcquireTrustPreferredInvestments" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:type="resource" xml:lang="en-US">Investment of cash in Trust Account</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_PaymentsToAcquireTrustPreferredInvestments" xlink:to="lab_us-gaap_PaymentsToAcquireTrustPreferredInvestments" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:to="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:label="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]</label>
    <label xlink:label="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">DESCRIPTION OF ORGANIZATION AND BUSINESS OPERATIONS</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:to="lab_us-gaap_OrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_RestatementOfPreviouslyIssuedFinancialStatementsAbstract" xlink:label="loc_atac_RestatementOfPreviouslyIssuedFinancialStatementsAbstract" xlink:type="locator"/>
    <label xlink:label="lab_atac_RestatementOfPreviouslyIssuedFinancialStatementsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restatement Of Previously Issued Financial Statements [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_RestatementOfPreviouslyIssuedFinancialStatementsAbstract" xlink:to="lab_atac_RestatementOfPreviouslyIssuedFinancialStatementsAbstract" xlink:type="arc"/>
    <label xlink:label="lab_atac_RestatementOfPreviouslyIssuedFinancialStatementsAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restatement of previously issued financial statements [Abstract].</label>
    <loc xlink:href="atac-20201231.xsd#atac_RestatementOfPreviouslyIssuedFinancialStatementsTextBlock" xlink:label="loc_atac_RestatementOfPreviouslyIssuedFinancialStatementsTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_RestatementOfPreviouslyIssuedFinancialStatementsTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Restatement Of Previously Issued Financial Statements [Text Block]</label>
    <label xlink:label="lab_atac_RestatementOfPreviouslyIssuedFinancialStatementsTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">RESTATEMENT OF PREVIOUSLY ISSUED FINANCIAL STATEMENTS</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_RestatementOfPreviouslyIssuedFinancialStatementsTextBlock" xlink:to="lab_atac_RestatementOfPreviouslyIssuedFinancialStatementsTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_RestatementOfPreviouslyIssuedFinancialStatementsTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Restatement of previously issued financial statements [Text block].</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AccountingPoliciesAbstract" xlink:label="loc_us-gaap_AccountingPoliciesAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AccountingPoliciesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Accounting Policies [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AccountingPoliciesAbstract" xlink:to="lab_us-gaap_AccountingPoliciesAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SignificantAccountingPoliciesTextBlock" xlink:label="loc_us-gaap_SignificantAccountingPoliciesTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Significant Accounting Policies [Text Block]</label>
    <label xlink:label="lab_us-gaap_SignificantAccountingPoliciesTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SignificantAccountingPoliciesTextBlock" xlink:to="lab_us-gaap_SignificantAccountingPoliciesTextBlock" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_InitialPublicOfferingAbstract" xlink:label="loc_atac_InitialPublicOfferingAbstract" xlink:type="locator"/>
    <label xlink:label="lab_atac_InitialPublicOfferingAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">INITIAL PUBLIC OFFERING</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_InitialPublicOfferingAbstract" xlink:to="lab_atac_InitialPublicOfferingAbstract" xlink:type="arc"/>
    <label xlink:label="lab_atac_InitialPublicOfferingAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">No definition available.</label>
    <loc xlink:href="atac-20201231.xsd#atac_InitialPublicOfferingTextBlock" xlink:label="loc_atac_InitialPublicOfferingTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_InitialPublicOfferingTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Initial Public Offering [Text Block]</label>
    <label xlink:label="lab_atac_InitialPublicOfferingTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">INITIAL PUBLIC OFFERING</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_InitialPublicOfferingTextBlock" xlink:to="lab_atac_InitialPublicOfferingTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_InitialPublicOfferingTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The entire disclosure on information about initial public offering.</label>
    <loc xlink:href="atac-20201231.xsd#atac_PrivatePlacementAbstract" xlink:label="loc_atac_PrivatePlacementAbstract" xlink:type="locator"/>
    <label xlink:label="lab_atac_PrivatePlacementAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">PRIVATE PLACEMENT</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_PrivatePlacementAbstract" xlink:to="lab_atac_PrivatePlacementAbstract" xlink:type="arc"/>
    <label xlink:label="lab_atac_PrivatePlacementAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">No definition available.</label>
    <loc xlink:href="atac-20201231.xsd#atac_PrivatePlacementTextBlock" xlink:label="loc_atac_PrivatePlacementTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_PrivatePlacementTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Private Placement [Text Block]</label>
    <label xlink:label="lab_atac_PrivatePlacementTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">PRIVATE PLACEMENT</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_PrivatePlacementTextBlock" xlink:to="lab_atac_PrivatePlacementTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_PrivatePlacementTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The entire disclosure on information about private placement.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RelatedPartyTransactionsAbstract" xlink:label="loc_us-gaap_RelatedPartyTransactionsAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transactions [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsAbstract" xlink:to="lab_us-gaap_RelatedPartyTransactionsAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:label="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transactions Disclosure [Text Block]</label>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">RELATED PARTY TRANSACTIONS</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:to="lab_us-gaap_RelatedPartyTransactionsDisclosureTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments and Contingencies Disclosure [Text Block]</label>
    <label xlink:label="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">COMMITMENTS AND CONTINGENCIES</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:to="lab_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockholdersEquityNoteAbstract" xlink:label="loc_us-gaap_StockholdersEquityNoteAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_StockholdersEquityNoteAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Note [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteAbstract" xlink:to="lab_us-gaap_StockholdersEquityNoteAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:label="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Stockholders' Equity Note Disclosure [Text Block]</label>
    <label xlink:label="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">SHAREHOLDERS' EQUITY</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:to="lab_us-gaap_StockholdersEquityNoteDisclosureTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueDisclosuresAbstract" xlink:label="loc_us-gaap_FairValueDisclosuresAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FairValueDisclosuresAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Disclosures [Abstract]</label>
    <label xlink:label="lab_us-gaap_FairValueDisclosuresAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Disclosures</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosuresAbstract" xlink:to="lab_us-gaap_FairValueDisclosuresAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueDisclosuresTextBlock" xlink:label="loc_us-gaap_FairValueDisclosuresTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Disclosures [Text Block]</label>
    <label xlink:label="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Disclosures</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosuresTextBlock" xlink:to="lab_us-gaap_FairValueDisclosuresTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsequentEventsAbstract" xlink:label="loc_us-gaap_SubsequentEventsAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SubsequentEventsAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Events [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsAbstract" xlink:to="lab_us-gaap_SubsequentEventsAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsequentEventsTextBlock" xlink:label="loc_us-gaap_SubsequentEventsTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SubsequentEventsTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsequent Events [Text Block]</label>
    <label xlink:label="lab_us-gaap_SubsequentEventsTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">SUBSEQUENT EVENTS</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsequentEventsTextBlock" xlink:to="lab_us-gaap_SubsequentEventsTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:label="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Basis of Accounting, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Basis of Presentation</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:to="lab_us-gaap_BasisOfAccountingPolicyPolicyTextBlock" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_EmergingGrowthCompanyPolicyTextBlock" xlink:label="loc_atac_EmergingGrowthCompanyPolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_EmergingGrowthCompanyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Emerging Growth Company [Policy Text Block]</label>
    <label xlink:label="lab_atac_EmergingGrowthCompanyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Emerging Growth Company</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_EmergingGrowthCompanyPolicyTextBlock" xlink:to="lab_atac_EmergingGrowthCompanyPolicyTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_EmergingGrowthCompanyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the accounting policy on Emerging Growth Company.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">New Accounting Pronouncements, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Recent Accounting Standards</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:to="lab_us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_UseOfEstimates" xlink:label="loc_us-gaap_UseOfEstimates" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_UseOfEstimates" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Use of Estimates, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_UseOfEstimates" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Use of Estimates</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UseOfEstimates" xlink:to="lab_us-gaap_UseOfEstimates" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:label="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:to="lab_us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_OfferingCostsPolicyTextBlock" xlink:label="loc_atac_OfferingCostsPolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_OfferingCostsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Offering Costs [Policy Text Block]</label>
    <label xlink:label="lab_atac_OfferingCostsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred Offering Costs</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_OfferingCostsPolicyTextBlock" xlink:to="lab_atac_OfferingCostsPolicyTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_OfferingCostsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the accounting policy on offering costs.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxPolicyTextBlock" xlink:label="loc_us-gaap_IncomeTaxPolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_IncomeTaxPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Income Tax, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_IncomeTaxPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Income Taxes</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncomeTaxPolicyTextBlock" xlink:to="lab_us-gaap_IncomeTaxPolicyTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EarningsPerSharePolicyTextBlock" xlink:label="loc_us-gaap_EarningsPerSharePolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_EarningsPerSharePolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_EarningsPerSharePolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net Income (Loss) Per Ordinary Share</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerSharePolicyTextBlock" xlink:to="lab_us-gaap_EarningsPerSharePolicyTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ConcentrationRiskCreditRisk" xlink:label="loc_us-gaap_ConcentrationRiskCreditRisk" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ConcentrationRiskCreditRisk" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Concentration Risk, Credit Risk, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_ConcentrationRiskCreditRisk" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Concentration of Credit Risk</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ConcentrationRiskCreditRisk" xlink:to="lab_us-gaap_ConcentrationRiskCreditRisk" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:label="loc_us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value of Financial Instruments, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Fair Value of Financial Instruments</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:to="lab_us-gaap_FairValueOfFinancialInstrumentsPolicy" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:label="loc_us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash and Cash Equivalents, Restricted Cash and Cash Equivalents, Policy [Policy Text Block]</label>
    <label xlink:label="lab_us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash and Marketable Securities Held in Trust Account</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:to="lab_us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_TemporaryEquitypolicyTextBlock" xlink:label="loc_atac_TemporaryEquitypolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_TemporaryEquitypolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Temporary Equity Policy Text Block</label>
    <label xlink:label="lab_atac_TemporaryEquitypolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class&#xA0;A Ordinary Shares Subject to Possible Redemption</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_TemporaryEquitypolicyTextBlock" xlink:to="lab_atac_TemporaryEquitypolicyTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_TemporaryEquitypolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Temporary Equity [Policy Text Block].</label>
    <loc xlink:href="atac-20201231.xsd#atac_LiabilityForWarrantsPolicyTextBlock" xlink:label="loc_atac_LiabilityForWarrantsPolicyTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_LiabilityForWarrantsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Liability For Warrants [Policy Text Block]</label>
    <label xlink:label="lab_atac_LiabilityForWarrantsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Warrant Liability</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_LiabilityForWarrantsPolicyTextBlock" xlink:to="lab_atac_LiabilityForWarrantsPolicyTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_LiabilityForWarrantsPolicyTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Liability for warrants.</label>
    <loc xlink:href="atac-20201231.xsd#atac_DisclosureOfRestatementsOfCertainAmountsInTheFinancialStatementsTableTextBlock" xlink:label="loc_atac_DisclosureOfRestatementsOfCertainAmountsInTheFinancialStatementsTableTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_DisclosureOfRestatementsOfCertainAmountsInTheFinancialStatementsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disclosure Of Restatements Of Certain Amounts In The Financial Statements [Table Text Block]</label>
    <label xlink:label="lab_atac_DisclosureOfRestatementsOfCertainAmountsInTheFinancialStatementsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disclosure Of Restatements Of Certain Amounts In The Financial Statements</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DisclosureOfRestatementsOfCertainAmountsInTheFinancialStatementsTableTextBlock" xlink:to="lab_atac_DisclosureOfRestatementsOfCertainAmountsInTheFinancialStatementsTableTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_DisclosureOfRestatementsOfCertainAmountsInTheFinancialStatementsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disclosure of restatements of certain amounts in the financial statements [Table text block].</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EarningsPerShareAbstract" xlink:label="loc_us-gaap_EarningsPerShareAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_EarningsPerShareAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings Per Share [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_EarningsPerShareAbstract" xlink:to="lab_us-gaap_EarningsPerShareAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]</label>
    <label xlink:label="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Earnings Per Share, Basic and Diluted</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:to="lab_us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_HeldToMaturitySecuritiesAbstract" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesAbstract" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_HeldToMaturitySecuritiesAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Held-to-maturity, Fair Value to Amortized Cost [Abstract]</label>
    <label xlink:label="lab_us-gaap_HeldToMaturitySecuritiesAbstract" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Fair Value Disclosures</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesAbstract" xlink:to="lab_us-gaap_HeldToMaturitySecuritiesAbstract" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_HeldToMaturitySecuritiesTextBlock" xlink:label="loc_us-gaap_HeldToMaturitySecuritiesTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_HeldToMaturitySecuritiesTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Held-to-maturity [Table Text Block]</label>
    <label xlink:label="lab_us-gaap_HeldToMaturitySecuritiesTextBlock" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Debt Securities, Held-to-maturity</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_HeldToMaturitySecuritiesTextBlock" xlink:to="lab_us-gaap_HeldToMaturitySecuritiesTextBlock" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_DisclosureOfAssumptionsUsedInEstimatingTheFairValueOfWarrantsTableTextBlock" xlink:label="loc_atac_DisclosureOfAssumptionsUsedInEstimatingTheFairValueOfWarrantsTableTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_DisclosureOfAssumptionsUsedInEstimatingTheFairValueOfWarrantsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disclosure Of Assumptions Used In Estimating The Fair Value Of Warrants [Table Text Block]</label>
    <label xlink:label="lab_atac_DisclosureOfAssumptionsUsedInEstimatingTheFairValueOfWarrantsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Assumptions Used In Estimating The Fair Value Of Warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DisclosureOfAssumptionsUsedInEstimatingTheFairValueOfWarrantsTableTextBlock" xlink:to="lab_atac_DisclosureOfAssumptionsUsedInEstimatingTheFairValueOfWarrantsTableTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_DisclosureOfAssumptionsUsedInEstimatingTheFairValueOfWarrantsTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disclosure of assumptions used in estimating the fair value of warrants.</label>
    <loc xlink:href="atac-20201231.xsd#atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTableTextBlock" xlink:label="loc_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTableTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disclosure Of Fair Value Measurement Of Assets And Liabilities Based On Hierarchy [Table Text Block]</label>
    <label xlink:label="lab_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule Of Fair Value Measurement Of Assets And Liabilities Based On Hierarchy</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTableTextBlock" xlink:to="lab_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTableTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Disclosure of fair value measurement of assets and liabilities based on hierarchy.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ScheduleOfChangesInFairValueOfWarrantLiabilitiesTableTextBlock" xlink:label="loc_atac_ScheduleOfChangesInFairValueOfWarrantLiabilitiesTableTextBlock" xlink:type="locator"/>
    <label xlink:label="lab_atac_ScheduleOfChangesInFairValueOfWarrantLiabilitiesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule Of Changes In Fair Value Of Warrant Liabilities [Table Text Block]</label>
    <label xlink:label="lab_atac_ScheduleOfChangesInFairValueOfWarrantLiabilitiesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Summary of changes in the fair value of warrant liabilities</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ScheduleOfChangesInFairValueOfWarrantLiabilitiesTableTextBlock" xlink:to="lab_atac_ScheduleOfChangesInFairValueOfWarrantLiabilitiesTableTextBlock" xlink:type="arc"/>
    <label xlink:label="lab_atac_ScheduleOfChangesInFairValueOfWarrantLiabilitiesTableTextBlock" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Schedule of changes in fair value of warrant liabilities.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:label="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:to="lab_us-gaap_SubsidiaryOrEquityMethodInvesteeSaleOfStockBySubsidiaryOrEquityInvesteeTable" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SubsidiarySaleOfStockLineItems" xlink:label="loc_us-gaap_SubsidiarySaleOfStockLineItems" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SubsidiarySaleOfStockLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Subsidiary, Sale of Stock [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SubsidiarySaleOfStockLineItems" xlink:to="lab_us-gaap_SubsidiarySaleOfStockLineItems" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_ThresholdMinimumAggregateFairMarketValueAsPercentageOfAssetsHeldInTrustAccount" xlink:label="loc_atac_ThresholdMinimumAggregateFairMarketValueAsPercentageOfAssetsHeldInTrustAccount" xlink:type="locator"/>
    <label xlink:label="lab_atac_ThresholdMinimumAggregateFairMarketValueAsPercentageOfAssetsHeldInTrustAccount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Threshold Minimum Aggregate Fair Market Value As A Percentage Of The Assets Held In The Trust Account</label>
    <label xlink:label="lab_atac_ThresholdMinimumAggregateFairMarketValueAsPercentageOfAssetsHeldInTrustAccount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Threshold minimum aggregate fair market value as a percentage of the assts held in the Trust Account</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ThresholdMinimumAggregateFairMarketValueAsPercentageOfAssetsHeldInTrustAccount" xlink:to="lab_atac_ThresholdMinimumAggregateFairMarketValueAsPercentageOfAssetsHeldInTrustAccount" xlink:type="arc"/>
    <label xlink:label="lab_atac_ThresholdMinimumAggregateFairMarketValueAsPercentageOfAssetsHeldInTrustAccount" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the threshold minimum aggregate fair market value as a percentage of the assets held in the Trust Account.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SharePrice" xlink:label="loc_us-gaap_SharePrice" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SharePrice" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share Price</label>
    <label xlink:label="lab_us-gaap_SharePrice" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Share price</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SharePrice" xlink:to="lab_us-gaap_SharePrice" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_ThresholdPercentageOfOutstandingVotingSecuritiesOfTargetToBeAcquiredByPostTransactionCompanyToCompleteBusinessCombination" xlink:label="loc_atac_ThresholdPercentageOfOutstandingVotingSecuritiesOfTargetToBeAcquiredByPostTransactionCompanyToCompleteBusinessCombination" xlink:type="locator"/>
    <label xlink:label="lab_atac_ThresholdPercentageOfOutstandingVotingSecuritiesOfTargetToBeAcquiredByPostTransactionCompanyToCompleteBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Threshold Percentage Of Outstanding Voting Securities Of The Target To Be Acquired By Post-Transaction Company To Complete Business Combination</label>
    <label xlink:label="lab_atac_ThresholdPercentageOfOutstandingVotingSecuritiesOfTargetToBeAcquiredByPostTransactionCompanyToCompleteBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Threshold percentage of public shares subject to redemption without the Company's prior written consent</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ThresholdPercentageOfOutstandingVotingSecuritiesOfTargetToBeAcquiredByPostTransactionCompanyToCompleteBusinessCombination" xlink:to="lab_atac_ThresholdPercentageOfOutstandingVotingSecuritiesOfTargetToBeAcquiredByPostTransactionCompanyToCompleteBusinessCombination" xlink:type="arc"/>
    <label xlink:label="lab_atac_ThresholdPercentageOfOutstandingVotingSecuritiesOfTargetToBeAcquiredByPostTransactionCompanyToCompleteBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the threshold percentage of outstanding voting securities of the target to be acquired by post-transaction company to complete business combination.</label>
    <loc xlink:href="atac-20201231.xsd#atac_MinimumNetTangibleAssetsUponConsummationOfBusinessCombination" xlink:label="loc_atac_MinimumNetTangibleAssetsUponConsummationOfBusinessCombination" xlink:type="locator"/>
    <label xlink:label="lab_atac_MinimumNetTangibleAssetsUponConsummationOfBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Minimum Net Tangible Assets Upon Consummation Of Business Combination</label>
    <label xlink:label="lab_atac_MinimumNetTangibleAssetsUponConsummationOfBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Minimum net tangible assets upon consummation of the Business Combination</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_MinimumNetTangibleAssetsUponConsummationOfBusinessCombination" xlink:to="lab_atac_MinimumNetTangibleAssetsUponConsummationOfBusinessCombination" xlink:type="arc"/>
    <label xlink:label="lab_atac_MinimumNetTangibleAssetsUponConsummationOfBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the minimum net tangible assets upon consummation of the Business Combination.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:label="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right, Exercise Price of Warrants or Rights</label>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Exercise price of warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:to="lab_us-gaap_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromIssuanceOfWarrants" xlink:label="loc_us-gaap_ProceedsFromIssuanceOfWarrants" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ProceedsFromIssuanceOfWarrants" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Issuance of Warrants</label>
    <label xlink:label="lab_us-gaap_ProceedsFromIssuanceOfWarrants" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Proceeds from issuance of warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromIssuanceOfWarrants" xlink:to="lab_us-gaap_ProceedsFromIssuanceOfWarrants" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AssetsHeldInTrust" xlink:label="loc_us-gaap_AssetsHeldInTrust" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AssetsHeldInTrust" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets Held-in-trust</label>
    <label xlink:label="lab_us-gaap_AssetsHeldInTrust" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets held in trust</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsHeldInTrust" xlink:to="lab_us-gaap_AssetsHeldInTrust" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_SaleOfStockUnderwritingFees" xlink:label="loc_atac_SaleOfStockUnderwritingFees" xlink:type="locator"/>
    <label xlink:label="lab_atac_SaleOfStockUnderwritingFees" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Underwriting fees</label>
    <label xlink:label="lab_atac_SaleOfStockUnderwritingFees" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Cash underwriting fees</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_SaleOfStockUnderwritingFees" xlink:to="lab_atac_SaleOfStockUnderwritingFees" xlink:type="arc"/>
    <label xlink:label="lab_atac_SaleOfStockUnderwritingFees" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the amount of underwriting fees incurred on sale of stock.</label>
    <loc xlink:href="atac-20201231.xsd#atac_UnitsIssuedDuringPeriodSharesNewIssues" xlink:label="loc_atac_UnitsIssuedDuringPeriodSharesNewIssues" xlink:type="locator"/>
    <label xlink:label="lab_atac_UnitsIssuedDuringPeriodSharesNewIssues" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Units Issued During Period, Shares, New Issues</label>
    <label xlink:label="lab_atac_UnitsIssuedDuringPeriodSharesNewIssues" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of units issued</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_UnitsIssuedDuringPeriodSharesNewIssues" xlink:to="lab_atac_UnitsIssuedDuringPeriodSharesNewIssues" xlink:type="arc"/>
    <label xlink:label="lab_atac_UnitsIssuedDuringPeriodSharesNewIssues" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of new units issued during the period.</label>
    <loc xlink:href="atac-20201231.xsd#atac_SaleOfStockOtherOfferingCosts" xlink:label="loc_atac_SaleOfStockOtherOfferingCosts" xlink:type="locator"/>
    <label xlink:label="lab_atac_SaleOfStockOtherOfferingCosts" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Other Offering Costs</label>
    <label xlink:label="lab_atac_SaleOfStockOtherOfferingCosts" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Other offering costs</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_SaleOfStockOtherOfferingCosts" xlink:to="lab_atac_SaleOfStockOtherOfferingCosts" xlink:type="arc"/>
    <label xlink:label="lab_atac_SaleOfStockOtherOfferingCosts" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the amount of other offering costs incurred on sale of stock.</label>
    <loc xlink:href="atac-20201231.xsd#atac_DeferredUnderwritingCompensationNoncurrent" xlink:label="loc_atac_DeferredUnderwritingCompensationNoncurrent" xlink:type="locator"/>
    <label xlink:label="lab_atac_DeferredUnderwritingCompensationNoncurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Underwriting Compensation, Noncurrent</label>
    <label xlink:label="lab_atac_DeferredUnderwritingCompensationNoncurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred underwriting fees</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DeferredUnderwritingCompensationNoncurrent" xlink:to="lab_atac_DeferredUnderwritingCompensationNoncurrent" xlink:type="arc"/>
    <label xlink:label="lab_atac_DeferredUnderwritingCompensationNoncurrent" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The carrying value as of balance sheet date of underwriting compensation deferred, classified as noncurrent.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ThresholdPercentageOfPublicSharesSubjectToRedemptionWithoutCompanysPriorWrittenConsent" xlink:label="loc_atac_ThresholdPercentageOfPublicSharesSubjectToRedemptionWithoutCompanysPriorWrittenConsent" xlink:type="locator"/>
    <label xlink:label="lab_atac_ThresholdPercentageOfPublicSharesSubjectToRedemptionWithoutCompanysPriorWrittenConsent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Threshold Percentage of Public Shares Subject to Redemption Without the Company's Prior Written Consent</label>
    <label xlink:label="lab_atac_ThresholdPercentageOfPublicSharesSubjectToRedemptionWithoutCompanysPriorWrittenConsent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Redemption threshold as percent of outstanding</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ThresholdPercentageOfPublicSharesSubjectToRedemptionWithoutCompanysPriorWrittenConsent" xlink:to="lab_atac_ThresholdPercentageOfPublicSharesSubjectToRedemptionWithoutCompanysPriorWrittenConsent" xlink:type="arc"/>
    <label xlink:label="lab_atac_ThresholdPercentageOfPublicSharesSubjectToRedemptionWithoutCompanysPriorWrittenConsent" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">This represents threshold percentage of Public Shares subject to redemption without the Company's prior written consent</label>
    <loc xlink:href="atac-20201231.xsd#atac_ThresholdBusinessDaysForRedemptionOfPublicShares" xlink:label="loc_atac_ThresholdBusinessDaysForRedemptionOfPublicShares" xlink:type="locator"/>
    <label xlink:label="lab_atac_ThresholdBusinessDaysForRedemptionOfPublicShares" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Threshold Business Days for Redemption of Public Shares</label>
    <label xlink:label="lab_atac_ThresholdBusinessDaysForRedemptionOfPublicShares" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Days for redemption of public shares</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ThresholdBusinessDaysForRedemptionOfPublicShares" xlink:to="lab_atac_ThresholdBusinessDaysForRedemptionOfPublicShares" xlink:type="arc"/>
    <label xlink:label="lab_atac_ThresholdBusinessDaysForRedemptionOfPublicShares" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the threshold business days for redemption of public shares.</label>
    <loc xlink:href="atac-20201231.xsd#atac_PercentageObligationToRedeemPublicSharesIfEntityDoesNotCompleteBusinessCombination" xlink:label="loc_atac_PercentageObligationToRedeemPublicSharesIfEntityDoesNotCompleteBusinessCombination" xlink:type="locator"/>
    <label xlink:label="lab_atac_PercentageObligationToRedeemPublicSharesIfEntityDoesNotCompleteBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage Obligation To Redeem Public Shares If Entity Does Not Complete A Business Combination</label>
    <label xlink:label="lab_atac_PercentageObligationToRedeemPublicSharesIfEntityDoesNotCompleteBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Obligation to redeem public shares if entity does not complete a business combination (as a percent)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_PercentageObligationToRedeemPublicSharesIfEntityDoesNotCompleteBusinessCombination" xlink:to="lab_atac_PercentageObligationToRedeemPublicSharesIfEntityDoesNotCompleteBusinessCombination" xlink:type="arc"/>
    <label xlink:label="lab_atac_PercentageObligationToRedeemPublicSharesIfEntityDoesNotCompleteBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the threshold percentage of Obligation to redeem Public Shares if entity does not complete a Business Combination.</label>
    <loc xlink:href="atac-20201231.xsd#atac_MaximumNetInterestToPayDissolutionExpenses" xlink:label="loc_atac_MaximumNetInterestToPayDissolutionExpenses" xlink:type="locator"/>
    <label xlink:label="lab_atac_MaximumNetInterestToPayDissolutionExpenses" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Maximum Net Interest to Pay Dissolution Expenses</label>
    <label xlink:label="lab_atac_MaximumNetInterestToPayDissolutionExpenses" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Maximum net interest to pay dissolution expenses</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_MaximumNetInterestToPayDissolutionExpenses" xlink:to="lab_atac_MaximumNetInterestToPayDissolutionExpenses" xlink:type="arc"/>
    <label xlink:label="lab_atac_MaximumNetInterestToPayDissolutionExpenses" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the maximum net interest to pay dissolution expenses.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IPOMember" xlink:label="loc_us-gaap_IPOMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_IPOMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">IPO [Member]</label>
    <label xlink:label="lab_us-gaap_IPOMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Initial Public Offering</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IPOMember" xlink:to="lab_us-gaap_IPOMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OverAllotmentOptionMember" xlink:label="loc_us-gaap_OverAllotmentOptionMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_OverAllotmentOptionMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Over-Allotment Option [Member]</label>
    <label xlink:label="lab_us-gaap_OverAllotmentOptionMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Over-allotment</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OverAllotmentOptionMember" xlink:to="lab_us-gaap_OverAllotmentOptionMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfErrorCorrectionsAndPriorPeriodAdjustmentRestatementTable" xlink:label="loc_us-gaap_ScheduleOfErrorCorrectionsAndPriorPeriodAdjustmentRestatementTable" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ScheduleOfErrorCorrectionsAndPriorPeriodAdjustmentRestatementTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Error Corrections and Prior Period Adjustment Restatement [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfErrorCorrectionsAndPriorPeriodAdjustmentRestatementTable" xlink:to="lab_us-gaap_ScheduleOfErrorCorrectionsAndPriorPeriodAdjustmentRestatementTable" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementLineItems" xlink:label="loc_us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementLineItems" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Error Corrections and Prior Period Adjustments Restatement [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementLineItems" xlink:to="lab_us-gaap_ErrorCorrectionsAndPriorPeriodAdjustmentsRestatementLineItems" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RestatementAxis" xlink:label="loc_srt_RestatementAxis" xlink:type="locator"/>
    <label xlink:label="lab_srt_RestatementAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revision of Prior Period [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RestatementAxis" xlink:to="lab_srt_RestatementAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RestatementDomain" xlink:label="loc_srt_RestatementDomain" xlink:type="locator"/>
    <label xlink:label="lab_srt_RestatementDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Revision of Prior Period [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RestatementDomain" xlink:to="lab_srt_RestatementDomain" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ScenarioPreviouslyReportedMember" xlink:label="loc_srt_ScenarioPreviouslyReportedMember" xlink:type="locator"/>
    <label xlink:label="lab_srt_ScenarioPreviouslyReportedMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Previously Reported [Member]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ScenarioPreviouslyReportedMember" xlink:to="lab_srt_ScenarioPreviouslyReportedMember" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_CurrentPeriodRestatementAdjustmentMember" xlink:label="loc_atac_CurrentPeriodRestatementAdjustmentMember" xlink:type="locator"/>
    <label xlink:label="lab_atac_CurrentPeriodRestatementAdjustmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Current Period Restatement Adjustment [Member]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_CurrentPeriodRestatementAdjustmentMember" xlink:to="lab_atac_CurrentPeriodRestatementAdjustmentMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:label="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued</label>
    <label xlink:label="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Unrecognized tax benefits accrued for interest and penalties</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:to="lab_us-gaap_UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_UnrecognizedTaxBenefits" xlink:label="loc_us-gaap_UnrecognizedTaxBenefits" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_UnrecognizedTaxBenefits" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Unrecognized Tax Benefits</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_UnrecognizedTaxBenefits" xlink:to="lab_us-gaap_UnrecognizedTaxBenefits" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount</label>
    <label xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Antidilutive securities excluded from the computation of earnings per share</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:to="lab_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AntidilutiveSecuritiesNameDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Antidilutive Securities, Name [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain" xlink:to="lab_us-gaap_AntidilutiveSecuritiesNameDomain" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_WarrantMember" xlink:label="loc_us-gaap_WarrantMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_WarrantMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Warrant [Member]</label>
    <label xlink:label="lab_us-gaap_WarrantMember" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Warrant</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WarrantMember" xlink:to="lab_us-gaap_WarrantMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:label="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Investment Income [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:to="lab_us-gaap_ScheduleOfInvestmentIncomeReportedAmountsByCategoryLineItems" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_WeightedAverageRedeemableClassaOrdinarySharesabstractAbstract" xlink:label="loc_atac_WeightedAverageRedeemableClassaOrdinarySharesabstractAbstract" xlink:type="locator"/>
    <label xlink:label="lab_atac_WeightedAverageRedeemableClassaOrdinarySharesabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average Redeemable ClassA Ordinary Shares Abstract [Abstract]</label>
    <label xlink:label="lab_atac_WeightedAverageRedeemableClassaOrdinarySharesabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Weighted Average Redeemable Class&#xA0;A Ordinary Shares</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_WeightedAverageRedeemableClassaOrdinarySharesabstractAbstract" xlink:to="lab_atac_WeightedAverageRedeemableClassaOrdinarySharesabstractAbstract" xlink:type="arc"/>
    <label xlink:label="lab_atac_WeightedAverageRedeemableClassaOrdinarySharesabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Weighted Average Redeemable Class&#xA0;A Ordinary Shares [Abstract].</label>
    <loc xlink:href="atac-20201231.xsd#atac_EarningsAllocableToRedeemableClassaOrdinarySharesabstractAbstract" xlink:label="loc_atac_EarningsAllocableToRedeemableClassaOrdinarySharesabstractAbstract" xlink:type="locator"/>
    <label xlink:label="lab_atac_EarningsAllocableToRedeemableClassaOrdinarySharesabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Earnings allocable to Redeemable ClassA Ordinary Shares Abstract [Abstract]</label>
    <label xlink:label="lab_atac_EarningsAllocableToRedeemableClassaOrdinarySharesabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Earnings allocable to Redeemable Class&#xA0;A Ordinary Shares</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_EarningsAllocableToRedeemableClassaOrdinarySharesabstractAbstract" xlink:to="lab_atac_EarningsAllocableToRedeemableClassaOrdinarySharesabstractAbstract" xlink:type="arc"/>
    <label xlink:label="lab_atac_EarningsAllocableToRedeemableClassaOrdinarySharesabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Earnings allocable to Redeemable Class&#xA0;A Ordinary Shares [Abstract].</label>
    <loc xlink:href="atac-20201231.xsd#atac_NetEarnings" xlink:label="loc_atac_NetEarnings" xlink:type="locator"/>
    <label xlink:label="lab_atac_NetEarnings" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Earnings</label>
    <label xlink:label="lab_atac_NetEarnings" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net earnings</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_NetEarnings" xlink:to="lab_atac_NetEarnings" xlink:type="arc"/>
    <label xlink:label="lab_atac_NetEarnings" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Net Earnings.</label>
    <loc xlink:href="atac-20201231.xsd#atac_NetLossMinusRedeemableNetEarningsabstractAbstract" xlink:label="loc_atac_NetLossMinusRedeemableNetEarningsabstractAbstract" xlink:type="locator"/>
    <label xlink:label="lab_atac_NetLossMinusRedeemableNetEarningsabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Net Loss minus Redeemable Net Earnings Abstract [Abstract]</label>
    <label xlink:label="lab_atac_NetLossMinusRedeemableNetEarningsabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Net Loss minus Redeemable Net Earnings</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_NetLossMinusRedeemableNetEarningsabstractAbstract" xlink:to="lab_atac_NetLossMinusRedeemableNetEarningsabstractAbstract" xlink:type="arc"/>
    <label xlink:label="lab_atac_NetLossMinusRedeemableNetEarningsabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Net Loss minus Redeemable Net Earnings [Abstract].</label>
    <loc xlink:href="atac-20201231.xsd#atac_RedeemableNetIncomeloss" xlink:label="loc_atac_RedeemableNetIncomeloss" xlink:type="locator"/>
    <label xlink:label="lab_atac_RedeemableNetIncomeloss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Redeemable Net Income Loss</label>
    <label xlink:label="lab_atac_RedeemableNetIncomeloss" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Redeemable Net Earnings</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_RedeemableNetIncomeloss" xlink:to="lab_atac_RedeemableNetIncomeloss" xlink:type="arc"/>
    <label xlink:label="lab_atac_RedeemableNetIncomeloss" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Redeemable Net Income (Loss).</label>
    <loc xlink:href="atac-20201231.xsd#atac_NonRedeemableNetIncomeloss" xlink:label="loc_atac_NonRedeemableNetIncomeloss" xlink:type="locator"/>
    <label xlink:label="lab_atac_NonRedeemableNetIncomeloss" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Non Redeemable Net Income Loss</label>
    <label xlink:label="lab_atac_NonRedeemableNetIncomeloss" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Non-Redeemable Net Loss</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_NonRedeemableNetIncomeloss" xlink:to="lab_atac_NonRedeemableNetIncomeloss" xlink:type="arc"/>
    <label xlink:label="lab_atac_NonRedeemableNetIncomeloss" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Non Redeemable Net Income (Loss).</label>
    <loc xlink:href="atac-20201231.xsd#atac_WeightedAverageNonredeemableClassbOrdinarySharesabstractAbstract" xlink:label="loc_atac_WeightedAverageNonredeemableClassbOrdinarySharesabstractAbstract" xlink:type="locator"/>
    <label xlink:label="lab_atac_WeightedAverageNonredeemableClassbOrdinarySharesabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Weighted Average NonRedeemable ClassB Ordinary Shares Abstract [Abstract]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_WeightedAverageNonredeemableClassbOrdinarySharesabstractAbstract" xlink:to="lab_atac_WeightedAverageNonredeemableClassbOrdinarySharesabstractAbstract" xlink:type="arc"/>
    <label xlink:label="lab_atac_WeightedAverageNonredeemableClassbOrdinarySharesabstractAbstract" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Weighted Average Non-Redeemable Class&#xA0;B Ordinary Shares [Abstract].</label>
    <loc xlink:href="atac-20201231.xsd#atac_RedeemableCommonClassAMember" xlink:label="loc_atac_RedeemableCommonClassAMember" xlink:type="locator"/>
    <label xlink:label="lab_atac_RedeemableCommonClassAMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Redeemable Common Class A [Member]</label>
    <label xlink:label="lab_atac_RedeemableCommonClassAMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Redeemable Common Class A</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_RedeemableCommonClassAMember" xlink:to="lab_atac_RedeemableCommonClassAMember" xlink:type="arc"/>
    <label xlink:label="lab_atac_RedeemableCommonClassAMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Redeemable Common Class A.</label>
    <loc xlink:href="atac-20201231.xsd#atac_NonRedeemableCommonClassBMember" xlink:label="loc_atac_NonRedeemableCommonClassBMember" xlink:type="locator"/>
    <label xlink:label="lab_atac_NonRedeemableCommonClassBMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Non Redeemable Common Class B [Member]</label>
    <label xlink:label="lab_atac_NonRedeemableCommonClassBMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Non Redeemable Common Class B</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_NonRedeemableCommonClassBMember" xlink:to="lab_atac_NonRedeemableCommonClassBMember" xlink:type="arc"/>
    <label xlink:label="lab_atac_NonRedeemableCommonClassBMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Non Redeemable Common Class B.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:label="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right, Number of Securities Called by Each Warrant or Right</label>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Shares issuable per warrant</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:to="lab_us-gaap_ClassOfWarrantOrRightNumberOfSecuritiesCalledByEachWarrantOrRight" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_NumberOfSharesIssuedPerUnit" xlink:label="loc_atac_NumberOfSharesIssuedPerUnit" xlink:type="locator"/>
    <label xlink:label="lab_atac_NumberOfSharesIssuedPerUnit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Shares Issued Per Unit</label>
    <label xlink:label="lab_atac_NumberOfSharesIssuedPerUnit" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of shares in a unit</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_NumberOfSharesIssuedPerUnit" xlink:to="lab_atac_NumberOfSharesIssuedPerUnit" xlink:type="arc"/>
    <label xlink:label="lab_atac_NumberOfSharesIssuedPerUnit" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the number of shares in a unit.</label>
    <loc xlink:href="atac-20201231.xsd#atac_NumberOfWarrantsIssuedPerUnit" xlink:label="loc_atac_NumberOfWarrantsIssuedPerUnit" xlink:type="locator"/>
    <label xlink:label="lab_atac_NumberOfWarrantsIssuedPerUnit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number of Warrants Issued Per Unit</label>
    <label xlink:label="lab_atac_NumberOfWarrantsIssuedPerUnit" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Number of warrants in a unit</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_NumberOfWarrantsIssuedPerUnit" xlink:to="lab_atac_NumberOfWarrantsIssuedPerUnit" xlink:type="arc"/>
    <label xlink:label="lab_atac_NumberOfWarrantsIssuedPerUnit" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the number of warrants in a unit.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromWarrantExercises" xlink:label="loc_us-gaap_ProceedsFromWarrantExercises" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ProceedsFromWarrantExercises" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds from Warrant Exercises</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ProceedsFromWarrantExercises" xlink:to="lab_us-gaap_ProceedsFromWarrantExercises" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:label="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Related Party Transactions, by Related Party [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:to="lab_us-gaap_ScheduleOfRelatedPartyTransactionsByRelatedPartyTable" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeAxis" xlink:label="loc_srt_RangeAxis" xlink:type="locator"/>
    <label xlink:label="lab_srt_RangeAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statistical Measurement [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeAxis" xlink:to="lab_srt_RangeAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember" xlink:label="loc_srt_RangeMember" xlink:type="locator"/>
    <label xlink:label="lab_srt_RangeMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Statistical Measurement [Domain]</label>
    <label xlink:label="lab_srt_RangeMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Statistical Measurement [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_RangeMember" xlink:to="lab_srt_RangeMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember" xlink:label="loc_srt_MaximumMember" xlink:type="locator"/>
    <label xlink:label="lab_srt_MaximumMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Maximum [Member]</label>
    <label xlink:label="lab_srt_MaximumMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Maximum</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_MaximumMember" xlink:to="lab_srt_MaximumMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RelatedPartyTransactionLineItems" xlink:label="loc_us-gaap_RelatedPartyTransactionLineItems" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transaction [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionLineItems" xlink:to="lab_us-gaap_RelatedPartyTransactionLineItems" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:label="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Consideration Received on Transaction</label>
    <label xlink:label="lab_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Consideration received</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:to="lab_us-gaap_SaleOfStockConsiderationReceivedOnTransaction" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:label="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sale of Stock, Number of Shares Issued in Transaction</label>
    <label xlink:label="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares issued</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:to="lab_us-gaap_SaleOfStockNumberOfSharesIssuedInTransaction" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_SharesTransferred" xlink:label="loc_atac_SharesTransferred" xlink:type="locator"/>
    <label xlink:label="lab_atac_SharesTransferred" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Shares Transferred</label>
    <label xlink:label="lab_atac_SharesTransferred" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares transferred</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_SharesTransferred" xlink:to="lab_atac_SharesTransferred" xlink:type="arc"/>
    <label xlink:label="lab_atac_SharesTransferred" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the number of shares transferred.</label>
    <loc xlink:href="atac-20201231.xsd#atac_AggregateOfSponsorSharesSurrendered" xlink:label="loc_atac_AggregateOfSponsorSharesSurrendered" xlink:type="locator"/>
    <label xlink:label="lab_atac_AggregateOfSponsorSharesSurrendered" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Aggregate Of Sponsor Shares Surrendered</label>
    <label xlink:label="lab_atac_AggregateOfSponsorSharesSurrendered" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares surrendered</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_AggregateOfSponsorSharesSurrendered" xlink:to="lab_atac_AggregateOfSponsorSharesSurrendered" xlink:type="arc"/>
    <label xlink:label="lab_atac_AggregateOfSponsorSharesSurrendered" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the number of common stock shares subject aggregate of sponsor surrendered.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination" xlink:label="loc_atac_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination" xlink:type="locator"/>
    <label xlink:label="lab_atac_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Threshold Period For Not To Transfer, Assign Or Sell Any Shares Or Warrants After Completion Of Initial Business Combination</label>
    <label xlink:label="lab_atac_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Threshold period for not to transfer, assign or sell any of their shares or warrants after the completion of the initial business combination</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination" xlink:to="lab_atac_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination" xlink:type="arc"/>
    <label xlink:label="lab_atac_ThresholdPeriodForNotToTransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The threshold period for not to transfer, assign or sell any of the shares or warrants, after the completion of the initial business combination.</label>
    <loc xlink:href="atac-20201231.xsd#atac_TransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombinationStockPriceTrigger" xlink:label="loc_atac_TransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombinationStockPriceTrigger" xlink:type="locator"/>
    <label xlink:label="lab_atac_TransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombinationStockPriceTrigger" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Transfer, Assign Or Sell Any Shares Or Warrants After Completion Of Initial Business Combination, Stock Price Trigger</label>
    <label xlink:label="lab_atac_TransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombinationStockPriceTrigger" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock price trigger to transfer, assign or sell any shares or warrants of the company, after the completion of the initial business combination (in dollars per share)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_TransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombinationStockPriceTrigger" xlink:to="lab_atac_TransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombinationStockPriceTrigger" xlink:type="arc"/>
    <label xlink:label="lab_atac_TransferAssignOrSellAnySharesOrWarrantsAfterCompletionOfInitialBusinessCombinationStockPriceTrigger" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Price of the entity's common stock which would be required to be attained to trigger the transfer, assign or sale of any shares or warrants of the company, after the completion of the initial business combination.</label>
    <loc xlink:href="atac-20201231.xsd#atac_MaximumCommonStockSharesSubjectToForfeiture" xlink:label="loc_atac_MaximumCommonStockSharesSubjectToForfeiture" xlink:type="locator"/>
    <label xlink:label="lab_atac_MaximumCommonStockSharesSubjectToForfeiture" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Maximum Common Stock, Shares Subject To Forfeiture</label>
    <label xlink:label="lab_atac_MaximumCommonStockSharesSubjectToForfeiture" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Shares subject to forfeiture</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_MaximumCommonStockSharesSubjectToForfeiture" xlink:to="lab_atac_MaximumCommonStockSharesSubjectToForfeiture" xlink:type="arc"/>
    <label xlink:label="lab_atac_MaximumCommonStockSharesSubjectToForfeiture" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the maximum number of common stock shares subject to forfeiture.</label>
    <loc xlink:href="atac-20201231.xsd#atac_NumberOfSharesNoLongerSubjectToForfeiture" xlink:label="loc_atac_NumberOfSharesNoLongerSubjectToForfeiture" xlink:type="locator"/>
    <label xlink:label="lab_atac_NumberOfSharesNoLongerSubjectToForfeiture" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Shares No Longer Subject To Forfeiture</label>
    <label xlink:label="lab_atac_NumberOfSharesNoLongerSubjectToForfeiture" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of shares no longer subject to forfeiture</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_NumberOfSharesNoLongerSubjectToForfeiture" xlink:to="lab_atac_NumberOfSharesNoLongerSubjectToForfeiture" xlink:type="arc"/>
    <label xlink:label="lab_atac_NumberOfSharesNoLongerSubjectToForfeiture" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of shares of the company that were no longer subject to forfeiture.</label>
    <loc xlink:href="atac-20201231.xsd#atac_NumberOfSharesForfeited" xlink:label="loc_atac_NumberOfSharesForfeited" xlink:type="locator"/>
    <label xlink:label="lab_atac_NumberOfSharesForfeited" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Number Of Shares Forfeited</label>
    <label xlink:label="lab_atac_NumberOfSharesForfeited" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of shares were forfeited</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_NumberOfSharesForfeited" xlink:to="lab_atac_NumberOfSharesForfeited" xlink:type="arc"/>
    <label xlink:label="lab_atac_NumberOfSharesForfeited" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Number of shares of the company that were forfeited during the period.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ThresholdPeriodAfterBusinessCombinationInWhichSpecifiedTradingDaysWithinAnySpecifiedTradingDayPeriodCommences" xlink:label="loc_atac_ThresholdPeriodAfterBusinessCombinationInWhichSpecifiedTradingDaysWithinAnySpecifiedTradingDayPeriodCommences" xlink:type="locator"/>
    <label xlink:label="lab_atac_ThresholdPeriodAfterBusinessCombinationInWhichSpecifiedTradingDaysWithinAnySpecifiedTradingDayPeriodCommences" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Threshold Period After Business Combination In Which Specified Trading Days Within Any Specified Trading Day Period Commences</label>
    <label xlink:label="lab_atac_ThresholdPeriodAfterBusinessCombinationInWhichSpecifiedTradingDaysWithinAnySpecifiedTradingDayPeriodCommences" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Threshold period after the business combination in which the 20 trading days within any 30 trading day period commences</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ThresholdPeriodAfterBusinessCombinationInWhichSpecifiedTradingDaysWithinAnySpecifiedTradingDayPeriodCommences" xlink:to="lab_atac_ThresholdPeriodAfterBusinessCombinationInWhichSpecifiedTradingDaysWithinAnySpecifiedTradingDayPeriodCommences" xlink:type="arc"/>
    <label xlink:label="lab_atac_ThresholdPeriodAfterBusinessCombinationInWhichSpecifiedTradingDaysWithinAnySpecifiedTradingDayPeriodCommences" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The threshold period after the business combination in which the 20 trading days within any 30 trading day period commences for the transfer, assigning or sale of any shares of the company, after the completion of the initial business combination.</label>
    <loc xlink:href="atac-20201231.xsd#atac_CommonStockSharesSubjectToForfeitureAsPercentOfIssuedAndOutstandingShares" xlink:label="loc_atac_CommonStockSharesSubjectToForfeitureAsPercentOfIssuedAndOutstandingShares" xlink:type="locator"/>
    <label xlink:label="lab_atac_CommonStockSharesSubjectToForfeitureAsPercentOfIssuedAndOutstandingShares" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock Shares Subject To Forfeiture As Percent Of Issued And Outstanding Shares</label>
    <label xlink:label="lab_atac_CommonStockSharesSubjectToForfeitureAsPercentOfIssuedAndOutstandingShares" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Common stock, shares subject to forfeiture, as a percent of issued and outstanding shares (as a percent)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_CommonStockSharesSubjectToForfeitureAsPercentOfIssuedAndOutstandingShares" xlink:to="lab_atac_CommonStockSharesSubjectToForfeitureAsPercentOfIssuedAndOutstandingShares" xlink:type="arc"/>
    <label xlink:label="lab_atac_CommonStockSharesSubjectToForfeitureAsPercentOfIssuedAndOutstandingShares" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">"Number of shares of the company that are subject to forfeiture represented as a percentage of issued and outstanding stock as a result of partial exercise of over-allotment option. "</label>
    <loc xlink:href="atac-20201231.xsd#atac_RelatedPartyLoansMember" xlink:label="loc_atac_RelatedPartyLoansMember" xlink:type="locator"/>
    <label xlink:label="lab_atac_RelatedPartyLoansMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Loans [Member]</label>
    <label xlink:label="lab_atac_RelatedPartyLoansMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Related Party Loans</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_RelatedPartyLoansMember" xlink:to="lab_atac_RelatedPartyLoansMember" xlink:type="arc"/>
    <label xlink:label="lab_atac_RelatedPartyLoansMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">This member stands for related party loans.</label>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_AffiliatedEntityMember" xlink:label="loc_srt_AffiliatedEntityMember" xlink:type="locator"/>
    <label xlink:label="lab_srt_AffiliatedEntityMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Affiliated Entity [Member]</label>
    <label xlink:label="lab_srt_AffiliatedEntityMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Affiliate</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_AffiliatedEntityMember" xlink:to="lab_srt_AffiliatedEntityMember" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_AdministrativeSupportAgreementMember" xlink:label="loc_atac_AdministrativeSupportAgreementMember" xlink:type="locator"/>
    <label xlink:label="lab_atac_AdministrativeSupportAgreementMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Administrative Support Agreement [Member]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_AdministrativeSupportAgreementMember" xlink:to="lab_atac_AdministrativeSupportAgreementMember" xlink:type="arc"/>
    <label xlink:label="lab_atac_AdministrativeSupportAgreementMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Administrative Support Agreement.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RelatedPartyTransactionSellingGeneralAndAdministrativeExpensesFromTransactionsWithRelatedParty" xlink:label="loc_us-gaap_RelatedPartyTransactionSellingGeneralAndAdministrativeExpensesFromTransactionsWithRelatedParty" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionSellingGeneralAndAdministrativeExpensesFromTransactionsWithRelatedParty" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transaction, Selling, General and Administrative Expenses from Transactions with Related Party</label>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionSellingGeneralAndAdministrativeExpensesFromTransactionsWithRelatedParty" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Administrative expenses - related party</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionSellingGeneralAndAdministrativeExpensesFromTransactionsWithRelatedParty" xlink:to="lab_us-gaap_RelatedPartyTransactionSellingGeneralAndAdministrativeExpensesFromTransactionsWithRelatedParty" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:label="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Related Party Transaction, Amounts of Transaction</label>
    <label xlink:label="lab_us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Face amount</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:to="lab_us-gaap_RelatedPartyTransactionAmountsOfTransaction" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NotesPayableCurrent" xlink:label="loc_us-gaap_NotesPayableCurrent" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_NotesPayableCurrent" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Notes Payable, Current</label>
    <label xlink:label="lab_us-gaap_NotesPayableCurrent" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Promissory note - related party</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_NotesPayableCurrent" xlink:to="lab_us-gaap_NotesPayableCurrent" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_MaximumLoansConvertibleIntoWarrants" xlink:label="loc_atac_MaximumLoansConvertibleIntoWarrants" xlink:type="locator"/>
    <label xlink:label="lab_atac_MaximumLoansConvertibleIntoWarrants" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">maximum Loans Convertible Into Warrants</label>
    <label xlink:label="lab_atac_MaximumLoansConvertibleIntoWarrants" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Maximum loans converted into warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_MaximumLoansConvertibleIntoWarrants" xlink:to="lab_atac_MaximumLoansConvertibleIntoWarrants" xlink:type="arc"/>
    <label xlink:label="lab_atac_MaximumLoansConvertibleIntoWarrants" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Maximum amount of Loans that may be convertible into warrants of the post-Business Combination entity.</label>
    <loc xlink:href="atac-20201231.xsd#atac_CommitmentsAndContingenciesTable" xlink:label="loc_atac_CommitmentsAndContingenciesTable" xlink:type="locator"/>
    <label xlink:label="lab_atac_CommitmentsAndContingenciesTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments And Contingencies [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_CommitmentsAndContingenciesTable" xlink:to="lab_atac_CommitmentsAndContingenciesTable" xlink:type="arc"/>
    <label xlink:label="lab_atac_CommitmentsAndContingenciesTable" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Discloses the commitment and contingencies information.</label>
    <loc xlink:href="atac-20201231.xsd#atac_CommitmentsAndContingenciesLineItems" xlink:label="loc_atac_CommitmentsAndContingenciesLineItems" xlink:type="locator"/>
    <label xlink:label="lab_atac_CommitmentsAndContingenciesLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Commitments And Contingencies [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_CommitmentsAndContingenciesLineItems" xlink:to="lab_atac_CommitmentsAndContingenciesLineItems" xlink:type="arc"/>
    <label xlink:label="lab_atac_CommitmentsAndContingenciesLineItems" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.</label>
    <loc xlink:href="atac-20201231.xsd#atac_DeferredFeePerUnit" xlink:label="loc_atac_DeferredFeePerUnit" xlink:type="locator"/>
    <label xlink:label="lab_atac_DeferredFeePerUnit" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Deferred Fee Per Unit</label>
    <label xlink:label="lab_atac_DeferredFeePerUnit" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Deferred fee per unit</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DeferredFeePerUnit" xlink:to="lab_atac_DeferredFeePerUnit" xlink:type="arc"/>
    <label xlink:label="lab_atac_DeferredFeePerUnit" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the deferred fee per unit.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:to="lab_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssets" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_ProformaEquityValue" xlink:label="loc_atac_ProformaEquityValue" xlink:type="locator"/>
    <label xlink:label="lab_atac_ProformaEquityValue" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proforma Equity Value</label>
    <label xlink:label="lab_atac_ProformaEquityValue" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proforma Equity</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ProformaEquityValue" xlink:to="lab_atac_ProformaEquityValue" xlink:type="arc"/>
    <label xlink:label="lab_atac_ProformaEquityValue" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Proforma Equity Value</label>
    <loc xlink:href="atac-20201231.xsd#atac_ProceedsFromPipeInvestors" xlink:label="loc_atac_ProceedsFromPipeInvestors" xlink:type="locator"/>
    <label xlink:label="lab_atac_ProceedsFromPipeInvestors" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Proceeds From PIPE Investors</label>
    <label xlink:label="lab_atac_ProceedsFromPipeInvestors" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Proceeds From PIPE Investors</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ProceedsFromPipeInvestors" xlink:to="lab_atac_ProceedsFromPipeInvestors" xlink:type="arc"/>
    <label xlink:label="lab_atac_ProceedsFromPipeInvestors" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Proceeds From PIPE Investors.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionSharePrice" xlink:label="loc_us-gaap_BusinessAcquisitionSharePrice" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_BusinessAcquisitionSharePrice" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Business Acquisition, Share Price</label>
    <label xlink:label="lab_us-gaap_BusinessAcquisitionSharePrice" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Business Acquisition, Share Price</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_BusinessAcquisitionSharePrice" xlink:to="lab_us-gaap_BusinessAcquisitionSharePrice" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfStockByClassTable" xlink:label="loc_us-gaap_ScheduleOfStockByClassTable" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ScheduleOfStockByClassTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Stock by Class [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfStockByClassTable" xlink:to="lab_us-gaap_ScheduleOfStockByClassTable" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfStockLineItems" xlink:label="loc_us-gaap_ClassOfStockLineItems" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfStockLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Stock [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfStockLineItems" xlink:to="lab_us-gaap_ClassOfStockLineItems" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockVotingRights" xlink:label="loc_us-gaap_CommonStockVotingRights" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_CommonStockVotingRights" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Common Stock, Voting Rights</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_CommonStockVotingRights" xlink:to="lab_us-gaap_CommonStockVotingRights" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightTable" xlink:label="loc_us-gaap_ClassOfWarrantOrRightTable" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightTable" xlink:to="lab_us-gaap_ClassOfWarrantOrRightTable" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightAxis" xlink:label="loc_us-gaap_ClassOfWarrantOrRightAxis" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightAxis" xlink:to="lab_us-gaap_ClassOfWarrantOrRightAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightDomain" xlink:label="loc_us-gaap_ClassOfWarrantOrRightDomain" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right [Domain]</label>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightDomain" xlink:to="lab_us-gaap_ClassOfWarrantOrRightDomain" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_PublicWarrantsMember" xlink:label="loc_atac_PublicWarrantsMember" xlink:type="locator"/>
    <label xlink:label="lab_atac_PublicWarrantsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Public Warrants [Member]</label>
    <label xlink:label="lab_atac_PublicWarrantsMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Public Warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_PublicWarrantsMember" xlink:to="lab_atac_PublicWarrantsMember" xlink:type="arc"/>
    <label xlink:label="lab_atac_PublicWarrantsMember" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents information pertaining to Public warrants.</label>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_StatementScenarioAxis" xlink:label="loc_srt_StatementScenarioAxis" xlink:type="locator"/>
    <label xlink:label="lab_srt_StatementScenarioAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Scenario [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_StatementScenarioAxis" xlink:to="lab_srt_StatementScenarioAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ScenarioUnspecifiedDomain" xlink:label="loc_srt_ScenarioUnspecifiedDomain" xlink:type="locator"/>
    <label xlink:label="lab_srt_ScenarioUnspecifiedDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Scenario [Domain]</label>
    <label xlink:label="lab_srt_ScenarioUnspecifiedDomain" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Scenario [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_srt_ScenarioUnspecifiedDomain" xlink:to="lab_srt_ScenarioUnspecifiedDomain" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds18.00Member" xlink:label="loc_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds18.00Member" xlink:type="locator"/>
    <label xlink:label="lab_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds18.00Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Redemption Of Warrants When Price Per Share Of Class Common Stock Equals Or Exceeds18.00 [Member]</label>
    <label xlink:label="lab_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds18.00Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Redemption of Warrants When the Price per Share of Class A Common Stock Equals or Exceeds $18.00</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds18.00Member" xlink:to="lab_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds18.00Member" xlink:type="arc"/>
    <label xlink:label="lab_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds18.00Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">This member stands for the scenario, where redemption of warrants when the price per share of class a common stock equals or exceeds $18.00.</label>
    <loc xlink:href="atac-20201231.xsd#atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds10.00Member" xlink:label="loc_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds10.00Member" xlink:type="locator"/>
    <label xlink:label="lab_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds10.00Member" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Redemption Of Warrants When Price Per Share Of Class Common Stock Equals Or Exceeds10.00 [Member]</label>
    <label xlink:label="lab_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds10.00Member" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Redemption of Warrants When the Price per Share of Class A Common Stock Equals or Exceeds $10.00</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds10.00Member" xlink:to="lab_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds10.00Member" xlink:type="arc"/>
    <label xlink:label="lab_atac_RedemptionOfWarrantsWhenPricePerShareOfClassCommonStockEqualsOrExceeds10.00Member" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">This member stands for the scenario, where redemption of warrants when the price per share of class a common stock equals or exceeds $10.00.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightLineItems" xlink:label="loc_us-gaap_ClassOfWarrantOrRightLineItems" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightLineItems" xlink:to="lab_us-gaap_ClassOfWarrantOrRightLineItems" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_ClassOfWarrantOrRightMinimumThresholdWrittenNoticePeriodForRedemptionOfWarrants" xlink:label="loc_atac_ClassOfWarrantOrRightMinimumThresholdWrittenNoticePeriodForRedemptionOfWarrants" xlink:type="locator"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightMinimumThresholdWrittenNoticePeriodForRedemptionOfWarrants" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class Of Warrant Or Right, Minimum Threshold Written Notice Period For Redemption Of Warrants</label>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightMinimumThresholdWrittenNoticePeriodForRedemptionOfWarrants" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Minimum threshold written notice period for redemption of public warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ClassOfWarrantOrRightMinimumThresholdWrittenNoticePeriodForRedemptionOfWarrants" xlink:to="lab_atac_ClassOfWarrantOrRightMinimumThresholdWrittenNoticePeriodForRedemptionOfWarrants" xlink:type="arc"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightMinimumThresholdWrittenNoticePeriodForRedemptionOfWarrants" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The minimum threshold period during which a written notice is required for redemption of warrants, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.</label>
    <loc xlink:href="atac-20201231.xsd#atac_WarrantsAndRightsOutstandingExercisableTermFromClosingOfInitialPublicOffering" xlink:label="loc_atac_WarrantsAndRightsOutstandingExercisableTermFromClosingOfInitialPublicOffering" xlink:type="locator"/>
    <label xlink:label="lab_atac_WarrantsAndRightsOutstandingExercisableTermFromClosingOfInitialPublicOffering" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Warrants And Rights Outstanding, Exercisable Term From Closing Of Initial Public Offering</label>
    <label xlink:label="lab_atac_WarrantsAndRightsOutstandingExercisableTermFromClosingOfInitialPublicOffering" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Public Warrants exercisable term from the closing of the initial public offering</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_WarrantsAndRightsOutstandingExercisableTermFromClosingOfInitialPublicOffering" xlink:to="lab_atac_WarrantsAndRightsOutstandingExercisableTermFromClosingOfInitialPublicOffering" xlink:type="arc"/>
    <label xlink:label="lab_atac_WarrantsAndRightsOutstandingExercisableTermFromClosingOfInitialPublicOffering" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The warrants exercisable term from the closing of the initial public offering, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.</label>
    <loc xlink:href="atac-20201231.xsd#atac_MaximumThresholdPeriodForRegistrationStatementToBecomeEffectiveAfterBusinessCombination" xlink:label="loc_atac_MaximumThresholdPeriodForRegistrationStatementToBecomeEffectiveAfterBusinessCombination" xlink:type="locator"/>
    <label xlink:label="lab_atac_MaximumThresholdPeriodForRegistrationStatementToBecomeEffectiveAfterBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Maximum Threshold Period For Registration Statement To Become Effective After Business Combination</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_MaximumThresholdPeriodForRegistrationStatementToBecomeEffectiveAfterBusinessCombination" xlink:to="lab_atac_MaximumThresholdPeriodForRegistrationStatementToBecomeEffectiveAfterBusinessCombination" xlink:type="arc"/>
    <label xlink:label="lab_atac_MaximumThresholdPeriodForRegistrationStatementToBecomeEffectiveAfterBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">"The maximum threshold period for registration statement to become effective after business combination, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. "</label>
    <loc xlink:href="atac-20201231.xsd#atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsStockPriceTrigger" xlink:label="loc_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsStockPriceTrigger" xlink:type="locator"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsStockPriceTrigger" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class Of Warrant Or Right, Redemption Of Warrants Or Rights, Stock Price Trigger</label>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsStockPriceTrigger" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Stock price trigger for redemption of public warrants (in dollars per share)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsStockPriceTrigger" xlink:to="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsStockPriceTrigger" xlink:type="arc"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsStockPriceTrigger" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Price of the entity's common stock which would be required to be attained to trigger the redemption of warrants.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ClassOfWarrantOrRightRedemptionPriceOfWarrantsOrRights" xlink:label="loc_atac_ClassOfWarrantOrRightRedemptionPriceOfWarrantsOrRights" xlink:type="locator"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionPriceOfWarrantsOrRights" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class Of Warrant Or Right, Redemption Price Of Warrants Or Rights</label>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionPriceOfWarrantsOrRights" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Redemption price per public warrant (in dollars per share)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ClassOfWarrantOrRightRedemptionPriceOfWarrantsOrRights" xlink:to="lab_atac_ClassOfWarrantOrRightRedemptionPriceOfWarrantsOrRights" xlink:type="arc"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionPriceOfWarrantsOrRights" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Redemption price per share or per unit of warrants or rights outstanding.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDays" xlink:label="loc_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDays" xlink:type="locator"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDays" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class Of Warrant Or Right, Redemption Of Warrants Or Rights, , Threshold Trading Days</label>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDays" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Threshold trading days for redemption of public warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDays" xlink:to="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDays" xlink:type="arc"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdTradingDays" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Threshold number of specified trading days for stock price trigger considered for redemption of warrants.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdConsecutiveTradingDays" xlink:label="loc_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdConsecutiveTradingDays" xlink:type="locator"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdConsecutiveTradingDays" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class Of Warrant Or Right, Redemption Of Warrants Or Rights, , Threshold Consecutive Trading Days</label>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdConsecutiveTradingDays" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Threshold consecutive trading days for redemption of public warrants</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdConsecutiveTradingDays" xlink:to="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdConsecutiveTradingDays" xlink:type="arc"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightRedemptionOfWarrantsOrRightsThresholdConsecutiveTradingDays" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Threshold number of specified consecutive trading days for stock price trigger considered for redemption of warrants.</label>
    <loc xlink:href="atac-20201231.xsd#atac_PercentageOfGrossProceedsOnTotalEquityProceeds" xlink:label="loc_atac_PercentageOfGrossProceedsOnTotalEquityProceeds" xlink:type="locator"/>
    <label xlink:label="lab_atac_PercentageOfGrossProceedsOnTotalEquityProceeds" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Percentage Of Gross Proceeds On Total Equity Proceeds</label>
    <label xlink:label="lab_atac_PercentageOfGrossProceedsOnTotalEquityProceeds" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Percentage of gross proceeds on total equity proceeds</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_PercentageOfGrossProceedsOnTotalEquityProceeds" xlink:to="lab_atac_PercentageOfGrossProceedsOnTotalEquityProceeds" xlink:type="arc"/>
    <label xlink:label="lab_atac_PercentageOfGrossProceedsOnTotalEquityProceeds" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Represents the percentage of gross proceeds on total equity proceeds.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_WarrantsAndRightsOutstandingTerm" xlink:label="loc_us-gaap_WarrantsAndRightsOutstandingTerm" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_WarrantsAndRightsOutstandingTerm" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Warrants and Rights Outstanding, Term</label>
    <label xlink:label="lab_us-gaap_WarrantsAndRightsOutstandingTerm" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Warrant term</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_WarrantsAndRightsOutstandingTerm" xlink:to="lab_us-gaap_WarrantsAndRightsOutstandingTerm" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_MaximumThresholdPeriodForFilingRegistrationStatementAfterBusinessCombination" xlink:label="loc_atac_MaximumThresholdPeriodForFilingRegistrationStatementAfterBusinessCombination" xlink:type="locator"/>
    <label xlink:label="lab_atac_MaximumThresholdPeriodForFilingRegistrationStatementAfterBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Maximum Threshold Period For Filing Registration Statement After Business Combination</label>
    <label xlink:label="lab_atac_MaximumThresholdPeriodForFilingRegistrationStatementAfterBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Threshold period for filling registration statement after business combination</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_MaximumThresholdPeriodForFilingRegistrationStatementAfterBusinessCombination" xlink:to="lab_atac_MaximumThresholdPeriodForFilingRegistrationStatementAfterBusinessCombination" xlink:type="arc"/>
    <label xlink:label="lab_atac_MaximumThresholdPeriodForFilingRegistrationStatementAfterBusinessCombination" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">The maximum threshold period for filing registration statement after business combination, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ClassOfWarrantOrRightAdjustmentOfRedemptionPriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice1" xlink:label="loc_atac_ClassOfWarrantOrRightAdjustmentOfRedemptionPriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice1" xlink:type="locator"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightAdjustmentOfRedemptionPriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice1" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right, Adjustment of Redemption Price of Warrants or Rights, Percent, Based On Market Value And Newly Issued Price 1</label>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightAdjustmentOfRedemptionPriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Adjustment of redemption price of stock based on market value and newly issued price 1 (as a percent)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ClassOfWarrantOrRightAdjustmentOfRedemptionPriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice1" xlink:to="lab_atac_ClassOfWarrantOrRightAdjustmentOfRedemptionPriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice1" xlink:type="arc"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightAdjustmentOfRedemptionPriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice1" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percentage of adjustment of redemption price of stock based on market value and newly issued price.</label>
    <loc xlink:href="atac-20201231.xsd#atac_ClassOfWarrantOrRightAdjustmentOfExercisePriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice" xlink:label="loc_atac_ClassOfWarrantOrRightAdjustmentOfExercisePriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice" xlink:type="locator"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightAdjustmentOfExercisePriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right, Adjustment of Exercise Price of Warrants or Rights, Percent, Based On Market Value And Newly Issued Price</label>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightAdjustmentOfExercisePriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Adjustment of exercise price of warrants based on market value and newly issued price (as a percent)</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_ClassOfWarrantOrRightAdjustmentOfExercisePriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice" xlink:to="lab_atac_ClassOfWarrantOrRightAdjustmentOfExercisePriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice" xlink:type="arc"/>
    <label xlink:label="lab_atac_ClassOfWarrantOrRightAdjustmentOfExercisePriceOfWarrantsOrRightsPercentBasedOnMarketValueAndNewlyIssuedPrice" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Percentage of adjustment of exercise price of warrants based on market value and newly issued price.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueDisclosureOfAssetAndLiabilityNotMeasuredAtFairValueTable" xlink:label="loc_us-gaap_FairValueDisclosureOfAssetAndLiabilityNotMeasuredAtFairValueTable" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FairValueDisclosureOfAssetAndLiabilityNotMeasuredAtFairValueTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Disclosure of Asset and Liability Not Measured at Fair Value [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosureOfAssetAndLiabilityNotMeasuredAtFairValueTable" xlink:to="lab_us-gaap_FairValueDisclosureOfAssetAndLiabilityNotMeasuredAtFairValueTable" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_AssetHeldInTrustAxis" xlink:label="loc_atac_AssetHeldInTrustAxis" xlink:type="locator"/>
    <label xlink:label="lab_atac_AssetHeldInTrustAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Held In Trust [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_AssetHeldInTrustAxis" xlink:to="lab_atac_AssetHeldInTrustAxis" xlink:type="arc"/>
    <label xlink:label="lab_atac_AssetHeldInTrustAxis" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Asset Held In Trust.</label>
    <loc xlink:href="atac-20201231.xsd#atac_AssetHeldInTrustDomain" xlink:label="loc_atac_AssetHeldInTrustDomain" xlink:type="locator"/>
    <label xlink:label="lab_atac_AssetHeldInTrustDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Held In Trust [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_AssetHeldInTrustDomain" xlink:to="lab_atac_AssetHeldInTrustDomain" xlink:type="arc"/>
    <label xlink:label="lab_atac_AssetHeldInTrustDomain" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Asset Held In Trust.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AssetHeldInTrustMember" xlink:label="loc_us-gaap_AssetHeldInTrustMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AssetHeldInTrustMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Held In Trust [Member]</label>
    <label xlink:label="lab_us-gaap_AssetHeldInTrustMember" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Asset Held In Trust</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetHeldInTrustMember" xlink:to="lab_us-gaap_AssetHeldInTrustMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FinancialInstrumentAxis" xlink:label="loc_us-gaap_FinancialInstrumentAxis" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FinancialInstrumentAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instrument [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FinancialInstrumentAxis" xlink:to="lab_us-gaap_FinancialInstrumentAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:label="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial Instruments [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:to="lab_us-gaap_TransfersAndServicingOfFinancialInstrumentsTypesOfFinancialInstrumentsDomain" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_USTreasurySecuritiesMember" xlink:label="loc_us-gaap_USTreasurySecuritiesMember" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_USTreasurySecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">US Treasury Securities [Member]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_USTreasurySecuritiesMember" xlink:to="lab_us-gaap_USTreasurySecuritiesMember" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:label="loc_us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:to="lab_us-gaap_FairValueDisclosureAssetAndLiabilityNotMeasuredAtFairValueLineItems" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_HeldToMaturitySecurities" xlink:label="loc_us-gaap_HeldToMaturitySecurities" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_HeldToMaturitySecurities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Debt Securities, Held-to-maturity</label>
    <label xlink:label="lab_us-gaap_HeldToMaturitySecurities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Amortized Cost</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_HeldToMaturitySecurities" xlink:to="lab_us-gaap_HeldToMaturitySecurities" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_InterestIncomeFromTrustPreferredSecurities" xlink:label="loc_atac_InterestIncomeFromTrustPreferredSecurities" xlink:type="locator"/>
    <label xlink:label="lab_atac_InterestIncomeFromTrustPreferredSecurities" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Interest Income From Trust Preferred Securities</label>
    <label xlink:label="lab_atac_InterestIncomeFromTrustPreferredSecurities" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Interest Income From Trust Preferred Securities</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_InterestIncomeFromTrustPreferredSecurities" xlink:to="lab_atac_InterestIncomeFromTrustPreferredSecurities" xlink:type="arc"/>
    <label xlink:label="lab_atac_InterestIncomeFromTrustPreferredSecurities" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Interest Income From Trust Preferred Securities.</label>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfWarrantOrRightOutstanding" xlink:label="loc_us-gaap_ClassOfWarrantOrRightOutstanding" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightOutstanding" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Class of Warrant or Right, Outstanding</label>
    <label xlink:label="lab_us-gaap_ClassOfWarrantOrRightOutstanding" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Class of warrants or rights outstanding</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ClassOfWarrantOrRightOutstanding" xlink:to="lab_us-gaap_ClassOfWarrantOrRightOutstanding" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_PrivatePlacementWarrantsMember" xlink:label="loc_atac_PrivatePlacementWarrantsMember" xlink:type="locator"/>
    <label xlink:label="lab_atac_PrivatePlacementWarrantsMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Private Placement Warrants [Member]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_PrivatePlacementWarrantsMember" xlink:to="lab_atac_PrivatePlacementWarrantsMember" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTable" xlink:label="loc_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTable" xlink:type="locator"/>
    <label xlink:label="lab_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTable" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disclosure Of Fair Value Measurement Of Assets And Liabilities Based On Hierarchy [Table]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTable" xlink:to="lab_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyTable" xlink:type="arc"/>
    <loc xlink:href="atac-20201231.xsd#atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyLineItems" xlink:label="loc_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyLineItems" xlink:type="locator"/>
    <label xlink:label="lab_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyLineItems" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disclosure Of Fair Value Measurement Of Assets And Liabilities Based On Hierarchy [Line Items]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyLineItems" xlink:to="lab_atac_DisclosureOfFairValueMeasurementOfAssetsAndLiabilitiesBasedOnHierarchyLineItems" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AssetsFairValueDisclosure" xlink:label="loc_us-gaap_AssetsFairValueDisclosure" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_AssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Assets, Fair Value Disclosure</label>
    <label xlink:label="lab_us-gaap_AssetsFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Assets, Fair Value Disclosure</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_AssetsFairValueDisclosure" xlink:to="lab_us-gaap_AssetsFairValueDisclosure" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LiabilitiesFairValueDisclosure" xlink:label="loc_us-gaap_LiabilitiesFairValueDisclosure" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_LiabilitiesFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Financial and Nonfinancial Liabilities, Fair Value Disclosure</label>
    <label xlink:label="lab_us-gaap_LiabilitiesFairValueDisclosure" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Liabilities, Fair Value Disclosure</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_LiabilitiesFairValueDisclosure" xlink:to="lab_us-gaap_LiabilitiesFairValueDisclosure" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueByAssetClassAxis" xlink:label="loc_us-gaap_FairValueByAssetClassAxis" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FairValueByAssetClassAxis" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Class [Axis]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueByAssetClassAxis" xlink:to="lab_us-gaap_FairValueByAssetClassAxis" xlink:type="arc"/>
    <loc xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:label="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:type="locator"/>
    <label xlink:label="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Asset Class [Domain]</label>
    <labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:to="lab_us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationByAssetClassDomain" xlink:type="arc"/>
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    <label xlink:label="lab_atac_CashAndMarketableSecuritiesHeldInTrustAccountMember" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Cash And Marketable Securities Held In Trust Account [Member]</label>
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