I booked a flight SEA-PHL-LIS thru AA (AS won't do it unless less than 2 weeks, miles only). I have been watching the SEA-PHL leg carefully, wishing to use a GGU on it. As far as I can tell AS442 never seems to get GGU availability.

According to the booking section of the AS website this flight has 3 available classes: Main, F and F upgrade. According to AS customer service the "upgrade" class does not grant you a F ticket but just a higher rank on the upgrade list.

Simply put, this sounds ridiculous - if you do not get the F upgrade AS keeps those funds, placating you with "you get get more miles out of the higher fare class".

Is this actually true or are the CS people wrong here?