If it is indeed the exact same heading -spelling, capitals, and all - then
you can record a macro with the following steps. Walk through these steps
BEFORE recording them, and USE A COPY of your document. These steps should
find the last heading in the document, select everything from that heading
to the end of the doc, cut it to the clipboard, open a new doc and paste it
in. If this works to your satisfaction, then turn on the macro recorder by
double-clicking the "REC" at the bottom of the Word window. Remember the
name you give the macro. The recorder turns off by clicking the square.
Ctrl+End
Ctrl+F
Select More, Select Up
Type in the heading
Enter
Escape
Shift+Ctrl+End
Ctrl+X
Ctrl+N
Ctrl+V
At this point, you would manually do a SaveAs, and name your new doc. If
you recorded that in the macro, too, then it would also save the name, and
each new doc would overwrite the previous one.
Macros can be accessed by Alt+F8. You can also go to
Tools>>Options>>Commands tab, select Macros on the left, select your macro
on the right and drag it up to a toolbar. That will create a button that
will fire the macro every time you need to create a new doc using the macro.
You can also go to Tools>>Options, Keyboard button, select Macros on the
left, select your macro on the right, and assign a keyboard combination to
run it without using the mouse.
HTH
Ed