AA confirmed my AS upgrade from PE to J on a BA flight back in April (before the no BA metal rule was enforced). They sent a concerning email saying to call last week, but the rep I talked to said it was fine and reconfirmed the reservation on BA metal in J.

5 days before departure AA issued a no notice downgrade and put me back to PE and I was juts lucky to see it. After an angry call to their call center they moved me to TATL on AA metal and forced open C space. Couple painful hours on the phone but at least was able to apply the benefit.