Originally Posted by
christep
In principle generally yes, but only if you can get to the lounge. The problem at JFK is that if you are flying AA domestic out of T8/9 there's no way you can get to the BA airside lounge in T7.
Good Point

I forgot about that. Even though I could get there early to get in there and transfer via airtrain, I'm guessing the FTA probably won't let me into Terminal 1 with an American Airlines tickets
But I should have no problem right though as a JAL OW sapphire getting into the AA Admiral Club, right? I know AA's can't get into AC w/o membership to AC or international ticket, but the same doesn't hold true for non-AA elites accessing AC on a domestic ticket.