Resetting Page Count and using Page x of xx

Using Native PDF in Guides in Cloud.

I have page numbering working fine in footer.

Bookmap has:

   Frontmatter, renders to 5 pages

   Body, renders to 10 pages

   Backmatter. renders to 5 pages

I restart page numbering after Frontmatter, so on page 6.

Paging in footer shows page 6 of 20, 7 of 20, etc.

Last page shows page 15 of 20.

Obviously, I don't want that because it looks like there are 5 pages missing. Native PDF is not resetting the total page count when the page number is reset.

Is this a bug or is there something I need to do?