In most cases publishers can simply edit a book detail by first logging into the store, then going to the admin page.
As the image shows, you will have a number of options for each book. The first one on the left is Edit.
The + sign on the right is for creating a new revision of a book. If you wish to change the file of the book, then you definitely need to create a new revision. However, you will only see the + command if the book has been downloaded at least once. Otherwise, you can still do the edit and add the new file.
