Gary Leff reports on this issue in Boarding Area:
http://viewfromthewing.boardingarea....nsive-tickets/
As he states, AA agents can avoid doing this, and the issue can be rectified.
Things get a little more complicated when you’re booked into Basic Economy on a sold out flight, you need an agent who understands how to temporarily oversell the flight in a higher booking class and then cancel out the B space.
And as we know some agents seem poorly versed, and the imposed QIK interface on Sabre may add a layer of difficulty.