If you do not change the encryption key, it will not update in the plan. But that will not do you any good if you cannot remember it. My recommendation is if you think you used a memorable passphrase (rather than a ransom alpha-numeric-symbol one), you try to run a test restore of a single, small file to see if you can figure it out. If not, then the encrypted backups cannot be restored. You could leave the backup in place if you think the key may come to you, but then you should create a second storage account to a different Bucket and update the backup plan to use that storage and enter a new encryption key. Or you can use the same storage account and just update the encryption key. Everything will be backed up with the key change and old files will age out according to your retention settings - even if some of them may not be able to be restored without the old key. You can also reach out to Support to see if they have any other recommendations for you. Thanks.