Yes, OV is a DL specific upgrade class and would doubt the flight is still AF coded. Most likely, that segment will earn based on fare paid prorated based on percentage of distance flown. If booked on delta.com on a DL PS fare as DL coded flights, the domestic segment would normally book into a DL C+ W/S class. But since OP booked on AF, that segment originally booked into an AF T Economy class since AF does not have any equivalent fare class for DL's C+ classes.