Dec. 5, SFO-PVG at T-36 mark, I was No.1 with a total of 24 people on the WL, and 36 J seats open.

Clearly, everyone would get upgraded but UA was not clearing upgrades (typical for China flights). I was booked in premium economy and 1K PP was applied.

Called GS, and asked if upgrade can be pushed as I wanted a better seat. The agent checked the PNR, and said it can't be done unless it's PP from GS.

This is news to me. In the past I have done this and the agents had no issue pushing the upgrades of a GS passenger even if the upgrade instruments were not from GS.

BTW, system cleared my upgrade 3 hours later, as expected.