I think I may have encountered the same/similar bug as @S80_UK.
I'm in the upgrading a parity drive - and successfully finished a parity rebuild yesterday morning onto the new drive (the plugin did not interfere with this operation)
Following the rebuild I manually initiated a non correcting check late last night - with "Use increments for Unscheduled Parity Check" set to no.
I logged in just now and found it had paused at my scheduled pause time of 9:30 AM this morning. I resumed it and it is working along. While I do have the temperature threshold pause enabled - I can say with confidence that my drives did not reach the threshold (server is in a cold new england basement) And the only pause I see in my syslog was at 9:30 AM.
I also have a parity.check.tuning.scheduled file instead of .unscheduled
I'll add that based off my (hopefully correct) memory, previous manual checks never got paused by the plugin - and I did update the plugin a few days ago - not sure what version I upgraded from - sorry
parity.check.tuning.progress.save
parity.check.tuning.scheduled
parity-checks.log
parity.check.tuning.cfg
parity.check.tuning.cron
parity.check.tuning.progress
cam-nas-diagnostics-20210226-1803.zip