I have had this issue since before Christmas. At first it was just happening on any thread I was on
I would scroll down as I am reading the posts and then the page would reload and I would then greet a message saying server issue.
It has started happening in threads I am just reading. Just happened when I was mid reply and lost the lot.
i have noticed that others seem to behaving similar issues and went to 25 posts per page but still getting the problem.