It's my first year as a 1K, so apologies on the n00bie post. I saw that there were two open first class seats on the UA seat selector a few days ago. I tried to apply my GPU and was wait listed. Today, I noticed that there was one open seat remaining in F, so I got nervous and called the 1K line to see if I could confirm my upgrade. However, they said that first class was sold out and that was the reason I was wait listed. She explained that the open seat was showing because someone does not have a seat assignment. I guess what I don't understand is that I'm still given an option to pay $1,200 to upgrade to that seat, which to me, doesn't mean it's "SOLD OUT." Could someone give me a brief explanation of how I might be able to get my GPU confirmed and what tool I can use to figure out the TRUE number of seats available in F? Thanks! If it helps, it's flight UA1587 (SFO-BOS) on 8/2/2012.