We've changed some parameters regarding the increasing number of 502 errors we see on the instance. We would kindly ask you to report us such 502 errors in the next few days with the exact time you see them.
We got no feedback on any 502 errors in the last 11 days so it looks like the problem is finally solved 🎉
The only problem is, we changed two things. We might change one back for a short period of time in the next few days to check which of both lead to the problem. So if you experience 502 errors it will only be for a short time but please still report them.