The system also keep a record of WHEN you first get on the upgrade list.
I just got off the phone with an agent to check my status (flight hasn't cleared at 72 hours.) She made a mistake and thought I wanted to upgrade my entire itinerary SFO-ORD-LHR including the international portion, so started to do so. Then I said, no I'm just interested in the domestic portion. She undid the international part (I hadn't paid) and apologized.
But when I signed back on I was no longer on the upgrade list for the domestic portion of the flight SFO-ORD.
I added myself back by checking the "request upgrade" check box on the res on aa.com.
Then to confirm I called back and the second agent said " Yes you are back on the list, and you are at the same place on the list as you were before. You went on the upgrade list on Dec 19th and 10:33pm. That's the time it uses evern if you are re-added"
SO....If you are on the upgrade list and get removed and readded you apparently keep the same original position based on time you first got on the list... Can anyone else confirm this happening to them?
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Another puzzle though is that neither the first nor the second agent could tell me how many other people were on the SFO-ORD upgrade list. The both said they could not see that screen or that info. Is this new or does it depend on who they are? It is now 30 hours to departure.