Apple's Advanced Data Protection bug was fixed in iOS 17.6.1 today

Apple releases iOS 17.6.1 for iPhone with important bug fixes
https://9to5mac.com/2024/08/07/ios-17-6-1-update-now-available-details/

Specifically it fixes Apple's Advanced Data Protection bug in iOS 17.6.

  "Advanced Data Protection is an optional feature that expands
   end-to-end encryption to a number of additional iCloud services,
   including iCloud device backups, Messages backups, Photos,
   and much more."
   <https://9to5mac.com/2022/12/07/apple-advanced-data-protection-encryption-imessage-more/>

   "Apple has also released iOS 16.7.10 for older iPhone models.
    This update, build number 20H350, includes bug fixes
    and other improvements."