Hi Peter,
EKPV seems to be shipping adat related to POs.
So you can consider the field LEDAT(Delivery Creation Date) for delta functionality.
After you create a generic extractor, select cal day for delta & the specific field as LEDAT.
Give safety interval upper limit as 1 day, this will bring the delta as of yesterday. Select new status for changed recs & be sure to load to DSO.
There is no other available field, you will have to design your delta based on LEDAT only.
Lets know if u need anything else.
BR,
Shreesh.