I have to give the SFO GS lobby agents kudos. I was going to miss my flight due to a meeting running late. I did a change through the app but only economy was available (I was on a Z fare). I accepted the economy fare but when I went through the lobby I asked about the one open seat in F. They made a call and got the fare bucket opened (only J was available). With the change to economy, I was #1 on the upgrade standby list but happy I didn't have to deal with that since I had originally purchased a first class fare. This was great service. They were friendly and happy to help. It's been a while but nice when it happens.