FYI: I am the developer of the Master Calendar app. My app is best for if you have 2+ tables within the same base that you want on one calendar. (2 tables shown is free, 3+ requires a subscription)
It sounds like you may have three separate bases that you’re trying to sync into one base/table somewhere. If that’s the case, you might be able to do this with Airtable’s native Syncing functionality:
Pro plans can have synced tables pull from up to three sources (search the support site for “multi-source” sync).
