Right, so this is not a Sync table as as Sync table can only have one source to mirror.
So yes, this is all about using Automations to do the mirroring.
You will have two relationships where the combines table is the Parent and the children will be each of the two separate calendars. That will allow you to put in an overnight safety net to maintain the combined table, in case any of the day time live Automations fail.
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Mark Shnier (YQC)
Quick Base Solution Provider
Your Quick Base Coach
http://QuickBaseCoach.commark.shnier@gmail.com
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