How to reset iBooks to eliminate PDF duplicates?
iBooks displays (lists) duplicates of many of my PDF files, which then also appear on my iDevices via iCloud Drive syncing. Deleting any one of the two file listings deletes both "copies." Adding even a revised version of the PDF file back to iBooks "resurrects" both listings, even when the updated file name, title and/or contents have been modified. In this case both, the older and the newer file will be listed separately and in icon view either the old cover, or a generic cover may appear. Double-clicking on either file, opens the same newer version. This is in-spite of the fact that only one file is present at
/Users/'USERNAME'/Library/Containers/com.apple.BKAgentService/Data/Documents/iBooks
Tried deleting all iBooks-related files and sub-folders in Preferences, Cookies and Containers folders, including the book files in BKAgentService and the hidden iCloud Drive/iBooks folders. Upon restart, all books are still listed, or the false duplicates will be listed after re-adding the PDFs. This, regardless of iBooks being enabled or disabled under iCloud Drive prefs.
How can I successfully reset iBooks and start from scratch without it "remembering" those duplicates and/or older metadata?
[The screenshot is of the duplicate listings (note differences in Author) and the hidden file folder (note NO duplicates there).]
macOS Sierra (10.12)