flyphilrun

Hello,

I've tried to search for this but not come up with anything too relevant.
I have a multi-sector J class itinerary booked with AA, which includes sectors on BA (4 European sectors) and AY (1 TATL sector)
So I actually have 2 questions :
1. I'd like to change the seat assignment given to me on the AY flight. The AY website won't allow me to do so. Is there anyway to do this?
2. I have an AA PNR and a BA PNR. The BA flights are the first two flights and the last two flights of the whole ten sector booking. For the first two flights there are no seats booked and I get the usual BA pay for seat process if I go on to BA.com. However BA.com only shows me the 5 outbound sectors on the BA PNR. I can't find my return sectors on BA.com and the two BA flights in that journey have seats already allocated in J ... Seems weird. Could it be possible that my AA PNR is actually two different BA PNRs? If so how can I find the second BA PNR?

Thanks