I spoke with a Global Moderator about it and we were advised to set our own local rules on our current thread.
Thread owners can set local rules, so if you do so, make sure the user is aware, ie stating so in the OP and sending them a PM, and if they continue to post, it is grounds for a ban.
best regards.
Yes, when you make a new thread. You can't just change or implement new rules when you feel like it.