If I go to the User Control Panel and click on attachments I am informed that I have uploaded 212 attachments. However, when I go to manage attachments (below in advanced) I only see 20 of them whereas before I saw all 212.
I wanted to attach an earlier image to a current post but can no longer do that.
There have been no changes over the last couple of days. The only thing I can think of is that page was maybe cached by your browser and it just refreshed.
That's very strange as it can't have been cached as the page didn't exist when I had 20 attachments (5 ish years ago). Having looked again it appears that the thing that was wrong was it failed to display the text "page 1 of 11" and the navigation arrows.