Hey @kodiak – Welcome to the Local Community Forums!
It’s hard to say exactly why this broke after an upgrade. There might be more info in the Local log which you can view by following this FAQ:
It’s possible that the version of Apache that comes with macOS was updated, and temporarily interfered with Local. But switching between nginx/apache in Local seems to have cleared things up.
I’d say a good habit to get into is stopping each Local site at the end of the day. This allows Local to export the DB and makes it easy to restore to a new site if anything does go wrong (like the computer decides to update and break things)