One of the risks of waiting to book your next cruise onboard is that prices when the itineraries are first released are at the cheapest. Depending on how much time elapses between the release and your cruise, and the popularity of that cruise, there may have been more than a few significant price jumps. It can often be better to book a cruise as soon as they are released, and then when you get on board, "re-shop" it with the agent, who can tell you if based on the current pricing it would be better to cancel your booked cruise and re-book on board for the 10% and OBC, or if it would be better to keep your original reservation. Also yes, as the PP mentioned yearly price increases right off the bat have been quite high.
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