What Margaret says is almost true. If this is a specific range of pages that
don't change, then you can use the IF field using an argument along the
lines if page numbers = page x-y, and use one set of H or F if it is true
and use another set of H or Fs is the answer is false. You'll find an
example of the IF field used to insert the filename and path on the last
page footer here http://word.mvps.org/faqs/tblsfldsfms/UpdateFilename.htm.
The problem will be if you edit the document and the page numbering changes!
Another approach may be to use the StyleRef to change the H&Fs. This may
work better for you.