Are you a Castaway Club member? If so, try (800) 449-3380. Otherwise, try (800) 951-3532. But with today being the day Silver members can book the newly opened dates, the lines have been really clogged up.
Unless it's for booking one of the new itineraries, or urgent for a cruise departing in the next few days... I suggest waiting until next week. DCL phones are going to be busy with the Silver CC opening day today, and general public opening day tomorrow. It may be quieter on Friday.
I'm going to take a wild guess that the 407 lines are probably jumped to the top of the cue - or have their own cue as DISNEY is not paying for those as they are for the 800 or 888 numbers...
I used to work in a hotel and they never had 800/888 numbers for reservations. People complained and complained, so finally one year, they decided to try it - thankfully not for Christmas packages - BUT had the lines set up so that anyone calling in using the area code got jumped to the front of the line. (Reservations were the only people who knew that.) The 800/888 number didn't last long because they got MORE complaints about the wait time AND it cost the hotel a LOT of money.
ETA: I have no proof of this with DCL, BUT I know I called the Castaway Club line (starts with 407) yesterday during lunch to change my cruise (NOT to a newly released one, just to get it done) and didn't have ANY hold. AT ALL.
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