I was able to upgrade to FC on the first flight out of SNA to IAH on a Friday in November. The counter opens at 6:00a and I was one of the first in line. I had a seat available upgrade from my Prestige Pack and got right in. Then our plane had to stand in line as all 10 or so of the 6:45a flights depart the gates to await the 7:00a curfew.