Originally Posted by
notquiteaff
Maybe, but the OP seems to consider using AA as the loyalty program and AS as the operating carrier for their domestic flights. So they would be using AA status on AS flights, and AA availability of upgrades shouldn't matter.
Will be below AS elites of the same OW tier for upgrades.
Only obvious reason to use AA in this scenario is if the OP has enough spend on AA credit cards to buy top tier status.