Agents shouldn't be tricking the system to upgrade. Other people who could be ahead of you such as a GS or 1K on a higher fare may not get their upgrades.

Upgrades will VERY often not happen until day of travel, ala "the gate dance" --- that's just a reality of the new upgrade process for UA.

The sweeps generally run at flight time starting 5 days prior. Closer in to the flight on date sweeps run more, however I'm not sure how often they do on say day of flight.

Also as many folks will tell you, R availability doesn't necessarily indicate PCU availability.


Now if you want to complain about TOD upgrades.... Well that's another story...