I know that there has been discussion about this on other threads, but I'm wondering if anyone has a definitive answer as to when Delta would upgrade a passenger on international flights. I had thought that it was only possible if a) you purchase a YBM ticket, b) if the flight is oversold and they would like to make room in coach, c) if you have high Medallion status. On a recent flight from ams-sea, I (GM) was upgraded at the gate with a coworker (PM) - we both had Q tickets and they reissued us C class tickets without any explanation other than that we had a seat change. When checking in online, my reservation clearly stated that I was was not upgrade eligible for this flight. It looked like the flight was pretty full. Is this a common situation or was I just very lucky? Thanks!