The immediate workaround is to create some more groups, but you’ll also need to add those to the support categories.
(When I’m not providing free support) I’m working on a plugin that will add a user to a group if they are a member of another (set of) group(s). If it existed, and you are hosted in such a way that you could use it, it might help.
If you’re self-hosted, I think you could modify your app.yml such that it edited settings.yml and made the limit whatever you wanted.