They are only offering gty rooms for most categories now. Only the lower categories do they allow you to choose an actual stateroom. So, either the boat is filling up or they just want you to gty a category. Most of the boat is gty now, but inside rooms are still available including cat 12 gty. If the boat was really full, they would not be offering cat 12 gty, but they still are. This tells me they will take anything they can get at this point. If the boat was full, you just would not see cat 12 gty offered any more, but you still do. What I really think is being that it is getting close to the cruise, they will begin to assign staterooms for all the gty people and they do not want people choosing staterooms and not following through with their total purchase. If they only allow you to gty a room, this takes any risk off of them in assigning rooms so your cat 12 gty room that will be assigned has not been reserved by someone already. I never sailed disney before, so I am not sure if this is a common thing or not, but I would bet it is. That is what I think at least.
Even cat 11 and 10 will no longer let you choose a room number, only in gty will they. I also tried on the april 24 cruise, same thing..they are only offering you gty rooms for almost every category. I find it hard to believe however they filled up the boats that were about 75% empty in only 3 weeks, but who knows.