Our hosting provider had a major issue with their US West-Coast operations around 16:00 UTC. They’re reporting that they’ve located the cause and resolved it as of 16:10 UTC.
We have noticed that during this period of time, the user would notice false offline alerts between <15:15 and 16:22 UTC>, some services, eg. Captive Portal, have been affected too.
All devices came back up at <16:22 UTC, 15 December 2021>.
Any inconvenience caused is much regretted.