Yea, this is the first time I've really had this problem. I am now inside the 48 hour window and still don't have my upgrade (even two agents were like 'hmmm that's strange, there are plenty of seats’ and told me not to worry, I’d get my upgrade).
I’m flying a route that always has availability in F and this is really surprising to me. I am all for AA trying to make more money, they need it, but it is sort of silly to hold at least half of F empty until 45 hours before a flight. Your chance of F walkups is very low even if this destination is only three hours from the Olympics.
I almost wonder if AA is having some IT problems. AA.com has been having quite a few service issues lately IME.