Originally Posted by shrididdy

I had this happen on a JFK-SFO recently. Got upgraded to business cabin at T-48 but couldn't get a seat assignment before or at checkin. Went to the gate at T-1 and it appears the business cabin was overbooked. Gate agent was all confused, and after I insisted a little, gave me a seat in the business cabin. Actually curious if worked only because it was a 3-cabin aircraft and she bumped someone else up to First, which was mostly empty, rather than bump me down.

My guess is their process for regular vs. lower-cost paid upgrades, now that they are aggressively pushing those, is not perfectly in sync.