Me again! To my knowledge, you need to make the reservation when you get on board. If you to the Lido buffet for lunch when you board, they will have a Supper Club table set up to show what the offer and take reservations at that time. We did this in August on the Alaska cruise and it was great. Enjoy.
Carnival Victory (Canada): August, 2006
Carnival Liberty (Eastern Caribbean): January, 2008
Carnival Pride (Mexican Riviera); August, 2008
Carnival Freedom (Western Caribbean): January, 2009
Carnival Legend (Western Caribbean): June, 2009
Carnival Spirit (Alaska): August, 2009
Carnival Victory (Southern Caribbean): January, 2010