[Qt-creator] Problems switching kit between 4.85 and 5.5

[Duane]

QtCreator on Linux with Qt 4.8.5 and Qt 5.5.1 installed.  We're moving 
our projects from Qt4 to Qt5.  U

I have QtCreator setup with a kit using each so I can support both for 
the moment.  Recently when trying to build Qt4 projects I'm getting 
errors in files like qheaderview.h  where it doesn't like 
setSectionsMovable() which replaced Qt4's setMovable(), so I can see 
it's getting the header.

But if I look at the Makefile generated it seems to have the correct 
information.  In the kit/version section I can see that the includes 
look correct.  Any idea why QtCreator is not getting the correct path?