In this case, your book already has an ISBN so we don't like to delete it. It may get pulled in from another database or users may wonder what happened to it.
Instead of deleting it I replaced the description with a note saying the paperback was indefinitely delayed and changed the publication date to 2020. Should you release the Paperback at a later time you, as the author, should be able to go in and update the publication date.
I also removed the cover image from the book. GR is pretty strict about not replacing covers, so this way if you choose to publish it later and with a different cover, librarians will know that it was not published with the current cover.
Instead of deleting it I replaced the description with a note saying the paperback was indefinitely delayed and changed the publication date to 2020. Should you release the Paperback at a later time you, as the author, should be able to go in and update the publication date.
I also removed the cover image from the book. GR is pretty strict about not replacing covers, so this way if you choose to publish it later and with a different cover, librarians will know that it was not published with the current cover.