Send emails only on commits to specific branches (BB-11787)

We have a few git repositories in our company. Our development model involves developing on our private branches and then merging those with master. The problem with bitbucket is that we get notification emails on commits to ALL branches not specific ones. This is affecting our workflows a lot and is a pain for people who want to keep an eye on repositories for spurios commits. We have tried numerous email filters to weed out private branches but they work as expected. We would ideally like to receive email notifications ONLY ON these type of branches

• master (i.e. a branch name matching a specificed name)
• release-branch-* (i.e. a branch name matching a specified regex)

This is very critical for our workflow.