Okay..
I have PM'ed the owners to try to find out what has happened. I have posted in the backroom as well, to see if maybe someone on staff has an idea.
I have noticed that it is not just posts, but also PM's after that time on Wednesday have disappeared. The site sputtered at one point a few days ago, was unavailable for a period of time, came back up shortly and then went down for close to 30 hours or so. And we also know there was a major roll back, possibly to get the site back to the stable point before whatever it is that happened actually happened. So that may explain the roll back. Speculation, but it is the best I can come up with as a possible explanation.
So, on behalf of the staff, I apologise for any inconvenience and we shall let you know what happened as soon as we find out ourselves.