I'm still trying to use my last RPU that expires 1/31. It doesn't help when UA sends out flights with empty seats in first! This seems to be what happened on 1/24 UA1759 DEN-TPA.

About 10 minutes before departure the upgrades screen on the app went from "Booked Full" to "Booked 17" and 3 seats became available on the seat map. Shortly after, the door was closed and we left with those 3 seats empty. Another gentleman in my row was #3 on the list, while I was #2. There were 28 people in total on the upgrade list, which I showed to the FA. Apparently the gate agents were concerned about leaving late, and chose to get the door closed on time instead of processing upgrades.

While I can understand the desire to leave on time, doing it at the expense processing the upgrade list doesn't seem quite right!