While not QR related, it is AA. I have a revenue J (I) ticket next week that was originally BA SEA-LHR-MXP, the return of an itinerary with the outbound flown in March. Do to a schedule change, I am now flying BA metal, YVR-LHR-MXP in full J class on AA codeshare flights.
Interestingly, there is no baggage allowance & BA wants to charge $70/$90/$170 = $330 for three bags. I am OWE. There was no issue selecting seats without fees.
No checked baggage allowance on BA in full J class.
So apparently this isn't just a QR J/F award issue.
James