The snapshot version is the master version - it’s what you would install if you were running normally. If you’re testing the bleeding edge with the security additions, then that’s in the development branch - it’s a major change, and you can’t swap between the branches.
The development branch is discussed here -:
Since you weren’t running this version previously, you can’t just change to it, so if you want to use the PRs off Cloudbees, then make sure they aren’t from the development branch - use the master branch (or just install through the UI and then you’re definitely ok 
).