Updating OS on previously encrypted full backup

[greengrass]

I recently updated from Big Sur to Monterey. I have a previously created encrypted bootable backup of Big Sur from SD 3.5. In a week or so after making sure Monterey isn't creating problems I would like to update my backup to Monterey. I know I have to do an erase then full backup to do so. My question is do I have to decrypt the existing backup first and then reencrypt it after the first backup. Or does the erase remove the encryption?

[dnanian]

Erase removes the encryption. You need to re-enable FileVault as explained in the blog post about the new version.