iCloud storage
Hi. If I upgrade to 200GB for a month and then I decide to cancel that subscription, will the remaining gigs that I have disappear and revert to 200GB or will I still have the 200 at my disposal?
Your plan will be changed to whatever level you downgrade to (e.g., from 200GB to 50GB or the free 5GB plan). Also see the following from Downgrade your iCloud storage - Apple Support
When you downgrade your iCloud storage plan, the storage decrease takes effect after your current monthly or annual subscription ends.*
If you downgrade or cancel your plan and your stored iCloud content exceeds your available storage, new photos and videos don’t upload to iCloud Photos, files don't upload in iCloud Drive, Messages in iCloud don't update, and your iOS devices don't back up. Learn how to manage your storage by deleting the information that you don't need anymore.
If you downgrade to the free iCloud Storage plan, you'll have 5GB of storage.