This is also an issue when installing master for testing.
I'm kind of tired of using "yum reinstall" or "yum downgrade" to install latest code from master replacing 3.6 install, because master version is sometimes older then 3.6 builds.
How about having 4.x.99 on master - meaning the development version, never change this version.
4.x buids will be numbered 4.x.0-98 - always older then master.
Or - use odd version for master, even versions for releases:
4.18.x - next stable versions
4.19.x - next dev versions
4.20.x - next stable versions
...
Nir