Many cruise lines are cutting back, particularly on fuel costs and what was usual practice in the past is now not so. This applies to the heating of water in the pools and often they are now not heated. So even if you have enjoyed the warmth of a pool in the past do not expect it now. Having said that, I cannot speak for all cruise ships and there will be exceptions to the rules. My last two cruises April and June of this year the pools were not heated but I suppose my total answer is .... I don't know ... Neil.
Thanks for that anyway i suppose i shall just have to take the plunge.....apologies for the dreadful pun.