Hmm you might be right. If I fly into PRG it's a couple hundred cheaper and better options if I book through BA vs AA. Apart from having money stuck with BA if I end up canceling, what are other implications of booking with BA?

How do I figure out what the loyalty points and award miles and does it depend who you book with, who operates the flight, or both (I understand how to figure it for AA on AA)? I'll have platinum and I'll be booking premium economy.

If I book with BA do I lose the ability to request 500 mile upgrades on any US connections? (not that it's really important, I just want to understand the differences).

I guess I would lose the double award miles from my credit card