Thanks Stephen (Fireboat)
It's that time of the year when Microsoft choose to release a raft of "improvements" which results in most other software having to update. Google Chrome has just updated today, again as did Edge this week. If your PC is going slow or exhibiting strange results I suggest you update. Don't forget to backup before you do though.
The site appears to be fully functioning at present but I'm sure members will let you know when it doesn't.
I don't envy your position as I have similar problems with my own Club's small website.