Sudden rise in 3xx/4xx forum errors

Our discourse forum logs indicate that the number of 3xx/4xx forum errors have sharply risen over the last week. As discourse hosts our forum, we cannot see detailed server logs. We’ve contacted discourse support, but in the meantime, has anyone seen strange 3xx/4xx forum errors? What’s the exact error message you are seeing? Where are you being redirected to?

The only error I sometimes get is when I try and access the site via https://juce.com/forum rather than https://forum.juce.com

Hmmmm, that wouldn’t show up in the discourse logs though as https://juce.com/forum is hosted by ROLI.