I have a domestic trip coming up in Jan and I am on a K fare. I used miles to upgrade and 3 of the 4 legs have cleared. I didn't clear on the first leg of the inbound which is a redeye on a 24F config 757 which I had expected b/c EF didn't have any G availability showing at the time of booking. EF is now showing 9 seats as occupied and 15 as open with G0, V0.

I know V codes and G code availability are two different things and for this situation I should care about G availability opening up. My question is... If I'm currently on the UG waitlist, will G availability always open up as V availability opens up closer to the upgrade window? Or is it possible that V becomes available and G doesn't? Who has priority for UG?... a DM or PM 5 days out going for V upgrade or someone upgrading with miles already on waitlist going for a G upgrade?

Happy New Year!