My specific question is about the number you get when you use the auto-check-in on return flights. I actually bought a 1st cabin on this trip, but I noticed that on my return, on an RJ jet that my seq number is 27. Considering that the flight starts in the Eastern time zone and not a hub, I kind of doubt that someone is routing thru here internationally- the only way someone could have checked in earlier.

The point is, that if seq number is the determining factor for upgrades, and I've been 1-3 on the list for a bunch of upgrades in the past- is auto check-in and with a high number for a plane with not that many seats causing me to miss close upgrades?

How does United's computer decide what order to auto-check in people at? Is setting an alarm and doing it manually a way to get a lower SEQ number?