I kept a watch on the Fantasy cruise we just took (just for curiosity) and it was strange how much it changed. One day all the Verandah rooms would be gone. The next day all the porthole rooms would be gone but there would be verandah rooms open, then the same for the inside rooms and concierge. It flip flopped again and again right up to within just a few days of the cruise. I didn't think it would change that much after the PIF date but it sure did! At one point all that was open was inside rooms and then over the next 2 weeks lots of other rooms opened up. I am not sure if was because people had to cancel (even last minute) due to unforeseen circumstances or if
DCL holds rooms and then releases them right before the sailing. Just keep checking......