Originally Posted by
beltway
As noted in the wiki above, there is
much simpler way to get your AA number into the PNR:
When finalizing the booking of your award ticket on the BA site, delete your BA Executive Club number from the frequent-flyer ID box. Once the ticket is issued, you can update the reservation on the AA site (using the record locator number provided by BA) to add your AAdvantage number.
I was unable to do this today. I deleted my BA number in the booking process, but it still stuck to the reservation. Was not able to change it with old standbys QR or RJ, but AY website worked.