I'll just mention that what I do is create a new master document that has the correct branches enabled. In addition to giving the new version of the document a new name, this is particularly useful when there are many branches. For example the paper version may have e.g. branches for Topic A and C while the tech report may have the branches Topics A-E all enabled. Even for a single branch I find this more convenient that digging around in the document settings.
-- John C. McCabe-Dansted PhD Student University of Western Australia