iCloud Sync and backup are different
From the app’s English Help & Guide · Reference release 1.0.1
iCloud Sync
Optional private CloudKit sync keeps Gentled records aligned across your Apple devices. Turning it on requires an app restart before the store changes.
Automatic recovery backups
Optional daily backups create a separate recoverable copy in your iCloud Drive when the system allows. They can remain off even when sync is on, or be enabled independently.
Manual backup and restore
Create a portable backup, inspect a selected backup before restoring, and use a safety copy if restore fails. Restore is disabled while iCloud Sync is requested or active to avoid conflicting sources of truth.