Hi SAPHR,
I understand that because of parallel run you have to work more. But i didnt understand about unavailability of data. If data is not available then how they are processing salary in legacy system.
Main focus of parallel run will be on Total Earning, deductions should match exactly with legacy payroll.
eg: for empl X HRA rented accommodation related expemtion given in legacy then you have to maintain IT0581 with same rent amount at any cost to match tax calculation and so on.
As ur nt going to perform financial posting, you have enough of time to match the legacy salary vrs SAP. Let them generate in legacy, thn generate thru sap compare total earnings and Tax wherever you fond difference, re-look into those cases for matchup.
Inconsistency may because of 580 series infotypes which you have correctly figure out and secondly because of Time related data like Lop and kind of...
Regards,
Jay