I'm certainly no lawyer, but I think the idea of "good faith" determines a lot of contract disputes no matter what's actually stated on the paper. Disney's policy for as many years as I can remember has been to allow reservations into the next calendar year under the stipulation that the rate is not final until that year's rates have been released. They can demonstrate that this is their past and current practice in court of law. You, also, have a good faith alternative: cancel your reservation. I don't think there's a court in the world that will make Disney adhere to this error in wording as they were not out to deceive you in any way.