Time Machine backup fails on macOS Tahoe (26.x) with Umbrel Samba share

[5dsadsa8ds]

Time Machine backups fail immediately after creating the initial backup folder on macOS Tahoe (version 26.x).

Symptoms:

• Backup starts
• Initial sparsebundle/folder is created
• Fails right away (no further progress)

This worked on previous macOS versions.
Likely cause:
Samba 4.22+ breaks Time Machine due to removed fruit:posix_rename option and rename behavior with open files.
Samba bug: https://bugzilla.samba.org/show_bug.cgi?id=15926
Samba patch: https://gitlab.com/samba-team/samba/-/merge_requests/4163
Fixed in Samba 4.22.6+ and 4.23.3+.
Suggestion:
Update the bundled Samba version in Umbrel to one that includes the fix (e.g., 4.22.6 or newer).
Environment:

Umbrel Home
macOS Tahoe 26.x
Samba share configured for Time Machine

Thanks!