May not be related to your situation, but I had a site that was on 16.14 that was fine until last week and then they started experiencing outages. Upgraded them to 16.16 the night before last to see if it would help, had another outage again today. Outage apparently lasts 5 or 10 minutes.
Checked the logs and it flapped ALL the active interfaces:
It's connected to a stack of 2960S switches and its logs show the link, fluttering at 9:27 then going down at 9:35 then coming back up at the time we see there in the Meraki log. The flutters don't show in the Meraki log, only the result of what appears to be all of the active interfaces resetting including the WAN links.
I opened a support case this AM, we'll see what's going on.