If the dimension configuration file and database differ in major version, they are incompatible and it may not be possible to initialize the Registry client at all (so a migration script will definitely be needed).
Modifications to dimension configuration already in repositories (as opposed to the defaults in
daf_butler) are effectively forks of the main configuration in
daf_butler, and should be versioned as X.Y.Z+dX.dY.dZ, where X.Y.Z is fixed at
daf_butler version at which it diverged, and dX.dY.dZ is the version of the fork (starting at 0.0.0).