Join Date: Nov 2018
Location: Istanbul, Turkey
Programs: TK Elite Plus,BAEC GGL,ITA Executive, AFKL Gold,QR Gold,HH Diamond,Bonvoy Gold,ALL Gold
Posts: 14,186
Indeed, you would not be able to benefit from cash upgrades or Avios upgrades if the flights are booked through AA.
It's very likely that you would be asked to pay the fare difference if you would like to upgrade to business.