Prefixed branched pull master on successful merge for white label?

[danthegoodmanicloud]

I was wondering if it was possible to setup something where any branch with a certain prefix (say `label/*`), could pull master every time there was a successful merge to master.

The reason I ask this is because I am working on a white label offering where clients have slight modifications of the front and back ends, which are compiled/statically rendered (would experience some slow downs from pulling in some dynamic data from say S3 or Redis), but all share the same base. Each of these white label instances could live in their own branch (prefix `label/instance_name`), and use pipelines to deploy their updates.

Maybe there is a better way to do trickle-down updates from merging to master, but I would love to automate those branches pulling down master on merge, so that the current white label instances would automatically update and deploy new versions.