I'm curious as to how people do this. I am interested in booking a cruise on board to take advantage of the discount/OBC/etc, but don't know the exact date or cruise we want to eventually take. If you have a party of 4 and you book a dummy cruise, do you have to rebook for a party of 4? Can you just book for a party of 1 or 2 and add guests later? We're unsure if we'll be taking an adults only cruise or the whole family.