Is it possible to disable the header on any page that has a Header 1?
The only way to do this automatically will be to write a macro. This is a bit beyond my macro skills, but this is the process you will need to follow as the only way to switch off a Header or Footer on a single page is by using Sections
Loop through each page
Check for a
Section Breakat top of current page
Section Breakat top of next page
Same As Previousfor BOTH the newly created sections
Headerof the current page
You may be able to get some help creating a macro on StackOverflow
You could also follow this process manually.
EDIT: In response to Comment:
Not quite - the "different footer and header" setting is only applicable to "odd and even" or "first page" e.g.:
page 1 has header a, all others have header b
even pages have header a, odd pages have header b
The only way to mix and match headers is to use section breaks with
Same As Previous switched off