Subscriptions sent to users who do not have a role with subscription permission

Issue Summary

We have roles that can receive subscriptions, however when that role expires users are still sent those subscriptions, although they cannot see or manage those subscriptions in their user account. Is there a way so that the subscriptions are only sent to users who have the permission to subscribe?

there seems to be no way of removing users who have subscribed to subscriptions by rules or vbo.