Layout Sheet Number not Editable

[KTBuilder]

For each one of my Plans, I sent to Layout, and just used the default Layout page.  I manually edited all the title block information on each Layout, instead of making a template.  Now I know better.

 

Problem is that all my Layout have sheet "A-1" in the lower right corner, and I am unable to edit that box.  All the others I can edit, but not the A-1.

 

I've got a ton of typed information on the Layout pages, so I don't want to lose that info if I re-send a Plan to Layout. 

 

I couldn't find anything in the Reference Manual, or searching the forum.  Any help will be appreciated.