You can currently book on
DCL's reservation site through April 2004. It may be "iffy" as to whether you would end up with the day at sea or the Freeport stop. DCL itineraries are subject to change, and that's a long way off. As their "Terms" state:
"<I>
Disney Cruise Line may in its sole discretion and without prior notice change, substitute, postpone, cancel, or deviate from any scheduled sailing, itinerary, or call at any port, and may substitute another vessel for the ship, and shall not be liable for any loss or damage incurred by Guest as a result of any such change, substitution, postponement, cancellation, or deviation</I>."
If it is a major concern but you really want to book it now, you should call DCL directly, express your concerns and ask for the specific planned itinerary for those dates.