So I'm on the PVG-SFO tomorrow with a Full BF and GF, but I'm number one on the UG. I doubt it will clear.

The later PVG-LAX (sorry I had SFO here) flight has 3 seats unsold in BF. Only middle E+ left.

I called the 1K line but they wouldn't give me any insights into the LAX flight upgrade list.

I'm on a V fare.

The 24 hr window for the LAX flight starts in about three hours.

Do I wait for 24hr to go and call in and see if they'll tell me what the UG list is composed of?
At 24hr, will that LAX flight fill out those seats to R and run the UG list- so if I wait to inside 24hrs I'll lose the chance at the UG.

The SFO flight is 7 hours earlier and I don't want to sit in a middle e+ for the 11hr LAX flight if I move over before the 24hr window to try to snag the UG and then get stuck.

Anyway to protect my aisle e+ seat on the SFO flight and dip my toe in the LAX flight UG pool and if it doesn't look like I'll make it, jump back.

That and I'm #1 on the SFO UG. I can hope someone gets held up immigration or traffic...