Make "Prefer sharps or flats" in "Part/Staff properties" apply to only selected measures

In the "Part/Staff properties" dialog box, there is an option to "Prefer sharps or flats for transposed key signatures". Sometimes a part will have different key signatures, and some will transpose correctly when you select "flat" and others when you choose "sharp". Can this be adjusted so that it can apply to only selected measures? For example, to prefer sharps in some measures and flats in others? The attached images are of an exercise I have been working on, that is a Bb Trumpet part where the key signature should be Gb for two measures and then B for two measures. I can get the Gb by selecting "prefer flats", but then the B is displayed as Cb. Thanks!