Originally Posted by GeoffR
I did a factory reset, reloaded the book from calibre, no changes to font settings or anything, but the problem still occurs with that book. It opens at a different pages, somewhere from page 153 to page 159, but never at page 160. The only thing I can think of is that if it is related to a chapter bug then this book doesn't have numbered chapters as such, only three parts appear in the TOC.
That was one of the things I was looking for. I have seen some other reports about reopening a page or two off. What I thought it could have been was a bit of inaccuracy the further the bookmark was from the reference point. That doesn't seem to be case.