Do_release_upgrade to ubuntu 16.04 messed up Nextcloud

Hi - I had a happy Nextcloud 10.0.2 running, when I decided it was time to upgrade 14.04 to 16.04. The process successfully upgraded the VM, but now just gives me the first-time setup page. Where should I begin my fix-it adventure?

Sounds like you need to start at the config file to ensure everything is still the same there, then head to the database and work your way out I guess.