Zoned pages in one or more editions?

This assumes that you will have a separate edition for each zone. All editions have to be in the same title.

As a consequence, if you deal with 2 zones, you will have 2 editions, and if you deal with 13 zones, you will have 13 editions. The list of pages of a single edition will not contain duplicated page numbers.

Yet, if you want to edit the editorial content of a page, it will be the same in which edition you will open it, since all of them are linked to each other.

As it is unlikely you will re-print the pages that stay the same between editions, zoned editions will typically not contain all the pages, but just the varied pages.

This assumes that the same edition will contain all the pages, for all the zones.

As a consequence, if you deal with 2 zones, the list of pages will contain two first pages, two second pages and so on. Yet, it will be the same which one you open to edit editorial content, since all of them are linked to each other.

It's not said that you need to have all pages duplicated - in an edition of 64 pages, you may have just 10 or 12 zoned pages.

Note: the fact that pages are duplicated does not mean that the content is duplicated. It's just that two pages will point to the same content.