Or even just a new installment. The first eight installments of ADF's Star Trek Log series had white covers with an actual TAS scene (usually from an episode adapted in the volume, though there might have been an exception) reproduced on the front cover. Then, for the last two volumes, Ballantine/Del Rey went to an illustration of the Enterprise at some odd angle, on a solid-color cover, a format they used for subsequent reprints of the first eight.
I'm really glad that (other than changing the back cover format) they didn't do that when they did a fully-illustrated TPB edition of the fourteen canonical Oz books: more-or-less the same slab-serif typeface, same color-on-color spine, same stunningly beautiful Michael Herring cover paintings, based on the original book illustrations.
Digital editions, unless the IP owner is a stickler for respecting the reader, are always subject to change (or even clawback). But print is forever (or at least, until the paper disintegrates).
And if my novel-in-progress ever sees distribution in digital form, you better believe it will be in a form that is immune to forced revisions or clawbacks. Even if I end up just putting a modification-protected PDF out under a Creative Commons "BY-ND" license.