Actually, I can't wait to remove it from my hard drive on Jan 1, since it's one of the most poorly designed apps I've ever used. It's really not surprising at all that they're not able to migrate it, assuming the quality of the app is indicative of the quality of the code. I wouldn't be surprised if the same was true of a lot of applications that are refusing to migrate. (I'll probably have to find an alternative to ebook-convert, the command line tool that's the only part of Calibre I use, or maybe I'll rewrite it in Python 3 myself.)