The Contract of Carriage with you implicitly agree to when you purchase airline tickets explicitly allows assessing a fuel surcharge at the gate. As far as I know, no major US domestic airline will offer passage without this tenet, however those that refuse to sell tickets until closer to the flight date are more likely to be flexible in that regard. But when you're selling tickets 11 months in advance, there are no guarantees: Not what times the flights will fly at, not what aircraft will be used, not with regard to the number of stops nor where, and not with regard to whether there will be a fuel surcharge or not.