Actually, I had to protect myself on DL on several occasions as cancellations/delays aren't always real-time events for reservations.

AA is the same way. If you're going to misconnect, just call the PLT line and they will protect you just as capably as the PM/GM line does at DL. The EXP desk is just as competent; they might be able to find upgrade inventory that the PLT desk 'misses' but that's about it...

Just like the CRC, it's a lot faster to call than it is to wait until you get to the AC.