My books got uploaded to iCloud and then disappeared. Can't find my 1000+ PDFs and epubs anywhere. I turned on an off, syncing, but to no avail. I updated iOS to 13.3, and the Apple Books automatically started uploading all my books to iCloud. The books were more than 15GB, and I had only 4 GB left in iCloud. I had the syncing turned off. But with the update to 13.3 iOS, it turned the syncing on, and now I have no way to find or retrieve my books. Walla! Magic. Great 'Jobs', Apple.
Can someone help me get my books back? Thank you.