I am just reporting this incase anyone else runs into the problem as I found a fix to get the schedule child site synching started again.
After updating to MainWP Dashboard v4.1.10, scheduled synching of Child Sites stopped. I could still synch fine manually.
The cron job mainwp_cronupdatescheck_action last run date was October 21 (even though it runs every minute, I know this date only updates when a synch actually happens). Also the action report also showed every minute it was checked:
CRON :: updates check :: waiting conditionals to run.
Anyways yesterday I decided to actually just resave my General Settings where the Synching frequency is set. This morning I checked and the automated synching had run. So this is the fix to get it started again.
So there appears to be a bug (at least for me) in the upgrade to 4.1.10 where the General Settings gets corrupted somehow and the Automatic Child Site Synching Scheduler can’t determine when to actually synch next.