I justs rebooked a cruise while on the Wonder and I had to put $250 per person as a deposit. I think it was higher ($500) if you wanted a cat 3 or higher room.
Another FYI....If you are going to rebook onboard, don't do what we did and wait until the end of the week. By Thursday, the line had a dozen people waiting to see one woman who does the rebooking.
Book early...you can always change the reservation at a later date if need be.
they don't advertise this but if you ask they'll let you do it -- you have 5 days to put down your deposit from the time you book -- we rebooked onboard the last night, disembarked on Thursday, and I called in the deposit to DCL on Saturday.
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