Calling all UA fare code experts. . .

I have booked a ticket from PIT-IAD-SFO in the A4BA3S fare basis. Since the first segment (PIT-IAD) is on UAX, the Booking Code is B, but the underlying fare basis is stil A4BA3S. Will I receive credit for the A (first) class of service bonus or only the B coach booking code on the UAX flight?

Same question the other way around. United is coming out with these YUP fare classes.

I have a ticket booked with the fare basis of YUAUP, but the booking code is A and the seat is in F Class. Do you think I will receive the F class of service bonus here or just the full-fare coach EQM bonus on the YUAUP?

Thanks for whatever help you can offer.