At the moment there are two branches: master (valid for the release up to 2.1.12) and 2.2.x (valid for the release from 2.2.x and up). I suggest to make master the default valid branch and only have a version based branches for the maintenance releases (until they expire when they should be deleted).
So right now we would rename the master to 2.1.x and the 2.2.x to master.
At the moment there are two branches: master (valid for the release up to 2.1.12) and 2.2.x (valid for the release from 2.2.x and up). I suggest to make master the default valid branch and only have a version based branches for the maintenance releases (until they expire when they should be deleted). So right now we would rename the master to 2.1.x and the 2.2.x to master.