I set up uptime kuma to also monitor certs this week when I got the reminder email about them stopping the email warnings, been using it for some time for uptime monitoring (mostly to see if some auto docker image update screws up my services) and the notification parts has worked nicely for that, so I’m also assuming it will work nicely for the certificates

BTW this is why it was stupid for all those government / emergency services accounts to resume posting on Twitter. Absolutely unreliable in critical situations