Interesting you say that. I have done tons of "fixes" directly with AA where they make a schedule change and revalidate the ticket and I dont like what they have done. Even with TA issued travel agents, I have dealt directly with them on things that fall squarely within the purview of their schedule change policy. That is not my question though, since the flight I want would not fall within the purview of the schedule change policy. But the fact that they have already changed the flight (to one I dont want) and reissued the ticket makes it clear they can actually make changes to a TA issued ticket.