RN104 Lost all snapshots, prune worker deleted them all

This post had been marked as spam and now it has been approved it's entered straight in to page 11.

Update:

I was cautious about making any changes until I had a better idea of what is going on here. Further information I have now is that no snapshots are now scheduled. I haven't altered the schedule since I set the unit up in 2015. Further entries to the log back to the firmware upgrades.

Tue Jan 2 2018 15:16:20
Backup: Successfully completed backup job Remote Backup.
Mon Jan 1 2018 0:09:22
Volume: Defragmentation complete for volume data.
Mon Jan 1 2018 0:00:06
Volume: Defragmentation started for volume data.
Sat Dec 30 2017 4:08:41
Snapshot: Snapshot prune worker successfully deleted snapshot 2017_11_04__00_00_53 from share or LUN Aivaf.
Tue Dec 26 2017 0:00:43
Volume: Balance complete for volume data.
Tue Dec 26 2017 0:00:07
Volume: Balance started for volume data.
Fri Dec 22 2017 12:47:14
Backup: Error backup job Remote Backup: Destination is read-only or files/folders could not be created. Check if these files or folders meet the destination file system limitation.
Mon Dec 18 2017 10:14:22
System: Application Contacts and Calendars Server is installed successfully.
Mon Dec 18 2017 9:11:04
Backup: Successfully completed backup job Remote Backup.
Sat Dec 16 2017 7:03:50
Snapshot: Snapshot prune worker successfully deleted snapshot 2017_10_21__00_00_18 from share or LUN Aivaf.
Mon Dec 11 2017 15:52:04
Backup: Successfully completed backup job Remote Backup (Off site drive).
Mon Dec 11 2017 9:02:26
Backup: Successfully completed backup job Remote Backup.
Sat Dec 9 2017 2:00:39
Snapshot: Snapshot prune worker successfully deleted snapshot 2017_10_14__00_00_58 from share or LUN Aivaf.
Mon Dec 4 2017 9:35:42
Backup: Successfully completed backup job Remote Backup.
Sat Dec 2 2017 7:58:09
Snapshot: Snapshot prune worker successfully deleted snapshot 2017_10_07__00_00_25 from share or LUN Aivaf.
Fri Dec 1 2017 6:58:12
System: A new firmware version (6.9.1) is available.
Fri Dec 1 2017 0:16:11
Volume: Defragmentation complete for volume data.
Fri Dec 1 2017 0:00:06
Volume: Defragmentation started for volume data.
Tue Nov 28 2017 9:24:35
Backup: Error backup job Remote Backup: Destination is read-only or files/folders could not be created. Check if these files or folders meet the destination file system limitation.
Sun Nov 26 2017 0:29:50
Volume: Balance complete for volume data.
Sun Nov 26 2017 0:00:01
Volume: Balance started for volume data.
Mon Nov 20 2017 8:32:49
Backup: Successfully completed backup job Remote Backup.
Sat Nov 18 2017 7:52:54
Snapshot: Snapshot prune worker successfully deleted snapshot 2017_09_23__00_00_26 from share or LUN Aivaf.
Fri Nov 17 2017 6:52:18
System: ReadyNASOS background service started.
Fri Nov 17 2017 6:52:10
System: Firmware was upgraded to 6.9.0.

Frustratingly I hadn't noticed the lack of snapshots being taken since the upgrade to 6.9.0