If you cancel you will be converted to free membership which includes 2gb of storage. If you have assets over this limit on the cloud you will get 90 days grace period to download it, after that you may lose access to some assets. See the following for official word
As the other 2 posts above have pointed out there are some steps you need to take before or just after you cancel your subscription and ONE you need to do right now. That one is make a Complete, Full, All inclusive Copy of all your images. Then make a copy of that copy of all your images.