ok...so I went back and 'sent to device' books whose titles I had changed.
original title: All I Ever Wanted
new title: 01All I Ever Wanted
What I ended up with was Calibre reading my device & telling me I had 2 books called 01All I Ever Wanted
but Nook showing All I Ever Wanted two times....no sign of a 01 anywhere.
(underline for reading ease only)
I'm going to go get caffeine and tackle this again. In the meantime any additioanl pointers would be appreciated.