How do I switch editions on the master page?

[Elizabeth]

I've recently switched publishers, which means a new ISBN and book cover. The old edition will no longer be available at the end of this month. However, all the covers that are in lists, on the main page, etc. still show the original edition. How do I go about putting the newest version as the default, and still have the old cover as just another edition? Here's the book:
The Light of Asteria: Kailmeyra's Last Hope

[rivka, Former Moderator]

You can't, currently. The default edition is the one that has been shelved/rated/reviewed by the most members. (Adding the ability for authors to change the default is something that has been discussed, and may become an available feature at some point in the future.)

[Elizabeth]

Thanks for letting me know. I'll quit trying to figure it out! I almost deleted the first, but then I thought that might be a really, really bad idea. :-)

[rivka, Former Moderator]

Yeah, please don't delete editions that are valid!