Another point to keep in mind, AS will sell up to the 50/65% right up to T-40 when the upgrade processing can start. So, if you really want FC, you need to "up fare" meaning pay the difference in cost fro what you paid for your seat and what FC is selling for when you make the purchase. As a 75kMM I have watched the available seats drop way down in the days before the flight. By doing a dummy booking you can usually tell if there really are any seats available or not, or if you have it use Expert Flyer to see what seats remain for sale.