Why do you want to create APD. You can create two reports and then schedule them for broadcast daily.
1st report having list of PO Numbers where data discrepancy is <= $5
2nd report having list of PO Numbers where data discrepancy is > $5
These both wold be identical reports just with the change in conditon.You can then use the broadcasting feature to distribute these reports to end user.It would save your time in unnecessary creating the APD.
You can also schedule the broadcst via PC if you want to send this information daily once the delta loads are finished.
Is there any specific reason you want to use APD ( for some calculation purpose) ?