It's hit and miss (mostly misses) with BA interlining especially at smaller stations. I have had BA contractor agent straight up telling me that she doesn't know how to interline a bag and that no BA staff was available. I've also had success at CDG but contractor agent took well over 20 minutes to tag one bag. It doesn't hurt to ask.
Depending on when you're flying, AS is supposedly moving to T1 sometimes next year which is only 5 minutes walk away from INTL Terminal.