The cruise industry has gone out of their way to make it appear by booking early such as a year in advance is the cheapest method. RCL on all of their lines such as Royal Carib, Celeb, Azam, etc has been a leader in doing so and going out of the their way to push this imho misinformation even going so far as to publish "news articles" stating this is the way to highest savings.

The industry goes out of their way not sell last minute cruises at a published discount. That being said you can still find discounts but the industry tries and limit availability or the notice to the general public.

Princes who owns Princess and Carnival started a program some time back for people to sign up for last minute offers..Not sure what happened to the program.