We're leaving on the 18th to the Bahamas.  I'll try to remember to let you know how far into the ship we are able to use it.  Based on conversations I've had with people, I'm figuring that by Tuesday, we should be able to use the pool. 

the water in the pool is changed every night so depending on where you are located will depend on how cold the water is going to be.  Kids sometimes do not mind that the water is cold. 

By Monday evening, some kids were swimming in the pool. Tuesday morning, the sun was shining bright and warm- deck was packed and pool was filling up.  People were even swimming through Saturday, so you should have happy children!  May be a little different come November, but I know I actually got sunburned from sitting out on the deck Tuesday, so it was definitely hot.  Have a great time.