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  <xsd:element id="fa_CapitalizedSoftwareDevelopedInternallyOrOtherwisePurchasedMember" name="CapitalizedSoftwareDevelopedInternallyOrOtherwisePurchasedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_ConcentrationRiskNumberOfCustomers" name="ConcentrationRiskNumberOfCustomers" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fa_FirstPortionOfCommonStockMember" name="FirstPortionOfCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_ImpactOfDividedToStockOptionAwardsAndESPPPurchases" name="ImpactOfDividedToStockOptionAwardsAndESPPPurchases" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fa_ClassALPUnitsClassBLPUnitsAndClassCLPUnitsMember" name="ClassALPUnitsClassBLPUnitsAndClassCLPUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_DeferredTaxes" name="DeferredTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fa_TermLoanDueJanuaryThirtyOneTwoThousandTwentySevenMember" name="TermLoanDueJanuaryThirtyOneTwoThousandTwentySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_ScheduleOfShareRepurchaseActivityTableTextBlock" name="ScheduleOfShareRepurchaseActivityTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fa_SummaryOfSignificantAccountingPoliciesLineItems" name="SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_SuccessorRevolverMember" name="SuccessorRevolverMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_SuccessorFirstLienCreditFacilityMember" name="SuccessorFirstLienCreditFacilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_AdditionalAssociatedCost" name="AdditionalAssociatedCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fa_InterestRateCollarsMember" name="InterestRateCollarsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_SilverLakeTransactionMember" name="SilverLakeTransactionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_ClassOneCommonStockMember" name="ClassOneCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_March2021UKAcquisitionMember" name="March2021UKAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_WorkingCapitalAndOtherTransactionAdjustments" name="WorkingCapitalAndOtherTransactionAdjustments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fa_OptionToPurchaseAdditionalSharesOfCommonStock" name="OptionToPurchaseAdditionalSharesOfCommonStock" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fa_PaymentsOnDeferredPurchaseAgreements" name="PaymentsOnDeferredPurchaseAgreements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fa_JosephJaeger1Member" name="JosephJaeger1Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_NetSettlementOfShareBasedCompensationPlanAwards" name="NetSettlementOfShareBasedCompensationPlanAwards" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fa_DividendsDeclaredButNotPaid" name="DividendsDeclaredButNotPaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fa_InternationalExceptUnitedStatesCanadaAndLatinAmericaMember" name="InternationalExceptUnitedStatesCanadaAndLatinAmericaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_StockRepurchasePricePerShare" name="StockRepurchasePricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fa_SuccessorFirstLienMember" name="SuccessorFirstLienMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_FastballHoldcoLPMember" name="FastballHoldcoLPMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_RecentAccountingPronouncementsPolicyTextBlock" name="RecentAccountingPronouncementsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fa_UnitedStatesCountryOfDomicileMember" name="UnitedStatesCountryOfDomicileMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCustomerLists" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedCustomerLists" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fa_CLPUnitsMember" name="CLPUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_UnderwritingDiscountsAndCommissions" name="UnderwritingDiscountsAndCommissions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fa_NoCustomersMember" name="NoCustomersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_CommonClassABCMember" name="CommonClassABCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_CostOfServicesExcludingDepreciationAndAmortization" name="CostOfServicesExcludingDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fa_InterestRateCollarMember" name="InterestRateCollarMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_StockOptionsPlanExpirationPeriod" name="StockOptionsPlanExpirationPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fa_JamesLClarkMember" name="JamesLClarkMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_AdditionalCompensationExpenses" name="AdditionalCompensationExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fa_JosephJaegerMember" name="JosephJaegerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_SharesRepurchasedAbstract" name="SharesRepurchasedAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_ProfitInterestUnits" name="ProfitInterestUnits" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fa_ShareRepurchaseProgramMember" name="ShareRepurchaseProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fa_ExercisePriceOfOutstandingStockOptionAwardsAndStockPurchases" name="ExercisePriceOfOutstandingStockOptionAwardsAndStockPurchases" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
</xsd:schema>
