If a bibliographer orders a new print edition of a book and indicates the earlier edition can be withdrawn, but that earlier edition has been designated an EAST retention commitment copy, do we have to keep the older edition or can we transfer the retention note to the newer edition?

If a bibliographer orders a new print edition of a book and indicates the earlier edition can be withdrawn, but that earlier edition has been designated an EAST retention commitment copy, do we have to keep the older edition or can we transfer the retention note to the newer edition?