Originally Posted by
link2
Sadly in my experience this isn't always true. The very first time I called the AA RTW desk, the agent refused to let me stop over in Asia both before/after visiting the SWP continent (a rule that was changed many years ago) and doubled down even after I pointed them to the relevant rule. Whilst the agents on the AA RTW desk are generally much more competent than your average reservations agent, HUACA is sometimes still necessary.
(I've since learned to avoid that particular agent, after they put me on an AA codeshare for a non-AA operated flight without even telling me during a simple date change - which then made it difficult to get back on the flight code I wanted!)
AA does not for all reservations, including non-RTW, if the flight is available. I've fed non-AA flight numbers to the agent, and they switch it to the AA code without asking and then play dumb when I ask for the non-AA flight number and tell them I wasn't on an AA code when I called in and didn't want an AA code now. Always ask them to hold it and then check on AA.com before you confirm the changes.