It could be as easy as adding some toggle to enable sending a patch series when you push to a specialy named branch, to relevant people (mentioned in the patch message for example, via Cc: tags).

Something like:

    git push master:email/v1

Email/v1 branch would not be created, it would just be a virtual target branch name for this functionality.

You can easily make a git hook script to do it with regular ssh/http based git hosting.