Originally Posted by Artpen100

I had set a Yapta alert to let me know if they first class price dropped on the flight, and got an email. I then confirmed it on UA.com with the "change flights" tab, though it wanted to charge me the 200 change fee (I seem to recall sometimes it doesn't, though I have not used that for some time.) First call, the agent wanted to charge me the "upgrade your flights" fee which had by then dropped from 800 to about 409. I think she did not bother to re-price it as a change on the same flight to a higher class as I had asked, and just looked at the upgrade line, so I just said "no thanks" and hung up. Second agent did re-price the flight in a higher fare class, but then said the fee was the 109 difference plus the 200 change fee. I then politely referred to the GG BUYUP rule, and she immediately removed the 200 change fee, making it 109.

This is a crazy system. You really have to know how it works to avoid paying more than you should.