Originally Posted by metallo

Generally, yes. Just make sure that, if it's a connecting itinerary, you're looking at the whole itinerary on EF, rather than individual flights (basically the opposite of what you'd do if you were searching SWU availability), because married segment logic does still apply to Airpass reservations.

In other words, you could pull up each flight of a two flight itinerary and might see J2D1I1 or something like that, but when you look at the whole connection, the same flight might be J2D0I0, and only full fare J (Airpass Business / domestic First, but not Instant Upgrade) will be available for purchase.

Originally Posted by metallo

Airpass flights credit to your AAdvantage account.

When you go through the booking process for Airpass, there is no option to change the frequent flyer number to another airline's loyalty program. The boxes for program and FF number are greyed out and cannot be modified.

I'm not sure what would happen if you tried to change your AA to BA number some other way (like asking an agent to do it at the airport just prior to departure), but I'm fairly certain AA's intention is not to allow that. I'd have to double check my contract, but there may even be some language there about the flights crediting to AA. (As an aside, previously, companion tickets would also be credited to the primary Airpass account holder's AA frequent flyer account, but now all passengers on a reservation earn their own miles/loyalty points, but those are still earned solely with AA.)

So, short answer, no -- everything credits to the respective personal AAdvantage account(s) of the individual(s) flying on Airpass, and you cannot change it to another airline during the booking process.