Thailand forum

Hi everyone, my boyfriend and I are going to be Phuket for a week in December (the height of peak season) and we wanted to go on a sea canoeing tour of Phang Nga Bay for a day. We will be staying at the Serenity Resort in Rawai near Chalong Bay for the first 4 days, then at the Belle Resort in Patong the last 3 days. we were told we wouldn't have to book tours in advance, but because we're traveling in peak season I'm a little nervous that everything might be booked up when we get there - should I book the Phang Nga Bay tour in advance, or just book it when I get there? Also, is it easier to get to Phang Nga Bay from Rawai (Chalong bay) or Patong? I'm trying to figure out if we should go on the tour during the first half of the trip, or the latter half of the trip when we are in Patong... thank you all so much for any information you can provide~