I'm pretty sure the answer to this is "no," but I thought I'd ask. Is it possible for Calibre (or a plugin somewhere) to check our Amazon library, find all books with updates (or are newer versions from what's in our Calibre library), download them in a non-KFX format, update the book in our Calibre library, and let us know what's changed?
There are an awful lot of my Amazon books out there with updates available. But, the thought of re-importing them gives me the heebie-jeebies.