There used to be a rally to the Andamans in Jan, but it stopped with the Tsuinami. I don't think it got up and running again.
google for 'Andaman sea rally"
The islands are fantastic - you must get a Andaman Islands specifc visa before you go (i.e. not just an
India visa) - you can get these in Bangkok.
Failing the rally, I'd put the word around the cruisers in Nai Harn bay Phuket - many are around in Nov / Dec and
head out to the Indian
Ocean crossing in Jan.
good luck