I agree with, so won't repeat, all the obvious statements about hurricane season and travel insurance. I book any time of the year, get the insurance and roll with the punches. More times than not I get to cruise and make most of the ports. It is a gamble, but the rates are great.
We missed Freeport on one cruise in May, pre-hurricane season. That morning it was so black, with heavy rain and thunderstorm. Boy we were upset that other ships docked and we didn't. Bummer. However, by 9:00 am our captain had us in beautiful blue water again under sunny skies and we had an extra sea day to just lounge under beautiful sunny skies, listening music and relaxing with a good book. Can't ask for more than that.
BTW, if you get the 20% discount, why not use it on a really great cruise in Europe, or upgrade your cabin to a balcony or suite.
Been there - done that:
2005 Holiday, Sensation, Conquest,
2006 Conquest, Celebration, Holiday,
2007 Freedom Grand Med, Holiday
2008 Fantasy & Sensation,
2009 Fantasy, Holiday & Dream Grand Med
2010 Fantasy and B2B Elation
2011 Monarch of the Seas
2012 Booked - Breeze from Barcelona 12 days