SnapRAID daily sync detects no changes unless I reboot

I have the SnapRAID plugin installed on OMV 4.x. I have enabled the script to run a daily sync very early every morning. I use automated download programs to fetch new media and I am notified on these events. At time when I am sure that new files have been added to my SnapRAID protected drives, the script will show a result of no files added/removed, and therefore, will skip the sync event. However, if I simply reboot and manually force the script to run again, the new files are found and the script completes correctly.

Any idea as to what could be happening that is fixed with a reboot?

The SnapRAID items in the system log presented in OMV's web UI just indicate that the diff was run, no changes were found, so the sync command was skipped. I had rebooted the system Friday before I posted my initial question, so it's been working correctly for a few days. When it eventually fails to detect new files, I'll have a look around for a more detailed log.