Though, I'd like to point out that the forum was not down at any time during this. It really was your browser having some kind of built-in blockage prohibiting you against your will to access the site. The site was up and provided perfectly functional HTTPS access as well as plain HTTP access throughout.

You might also consider that there is no additional security for this site in having an SSL certificate that is less than 3 months old. Still, there's also no particular reason in having one that is older (especially with some 30000 or more python code lines there to help us automating its update)

I would have tried to raise a ticket when I first noticed (about 9:05 GMT, so after only 15 minutes after the Certificate expired) but with the forum down I had no idea who to contact or how.

The support team sends their Thanks for the intended heads-up (even though they managed to get their shit together on their own this time).

Not sure when it got renewed, but obviously it's now been renewed.

Is there some reason why its not set up to renew before expiry? I assume it's a certbot cron job.