Also, you may not want to rush to cancel because once you cancel you have a year to use the replacement week, so the later you cancel the more you extend the life of the replacement week. However, make sure you cancel at least 60 days prior, so you don't get a replacement week good for flex change only.
The advantage of canceling is that you can place an ongoing request and / or grab the two bedroom right away online when the bulk deposit happens. If you have not canceled yet and the bulk occurs at 3 am, you can't book anything until II opens, and by then us vultures will have grabbed the best weeks. In that case you have the option to use another week, like your float week, to grab the two bedroom you want, then call II when they open and tell them to cancel that and rebook it with your December trade.