I have messaged Kobo about this but have got better and faster info from this forum. I upgraded my Kobo and my mother's yesterday (both originals). The process went ok. In both cases the books that we had been reading were still shown. On my mother's I use my account so we share the purchases. I synchronized new content to hers after the upgrade. It took less time but rearranged things

. New content did get added but some things previously added but not yet opened are now Locked. Following Kobo's suggestion to Refresh the library has not made a difference.
On my own device I have not added new content since upgrading. On mine the book I'm reading seems to be quite messed up. Text looks normal but I keep re-reading passages that I just read. With some books, on both devices, looking at the Table of contents shows that is out of order too. Things don't look to be completely corrupted but they sure are not normal. This is not what I was hoping for! Suggestions appreciated.
Kathy, Ottawa, Canada