If you're on an individual annual plan, we'll email you in advance of your plan renewing. We don't do that for monthly subscriptions (but you do get a receipt every month), and you can cancel your subscription at any time.
Once you've cancelled your plan, you will revert back to the 1 library and 40 books plan. All the books you've created will still be accessible to you, we never delete your books when a plan ends.
Let's say you were on the paid plan, you may have created 3 libraries with 100 books made across all three libraries. You won't be able to create any more books because your total limit is now 40 books.
So, you'll need to archive these libraries. You can archive all of them and then create a fresh new library with 40 books allocation, or you can archive two of the libraries and leave one library to work in that (as long as that library currently has less than 40 books in it).