RH page suddenly has gutter margin on RHS??

[LesCM19]

What on Earth have I done now?

The master pages of 95% of the contents have headers, footers & page numbering. They are all fine and unaffected by this. However the last few pages contain reference tables and as such I created different L&R masterpages with the same background but with no header, footer & page numbering.

I now notice that there are gutter margins on the RH edge of the RH page. I did not notice them before, I may have had Guides hidden.

Am I going to have to delete and redo the last few pages of the book?

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