Same as when they last banned a breed. They must all be registered, muzzled, and neutered. If not, fines/seizure and possible imprisonment of the owner.
Apart from because it's not a real bread, people will argue that it's not a bully wasting police time and effort having to seize and then categorise... time and money an already skint police force aren't going to want to do
I assume that it applies to the dog in public, not while in your house. Even if it doesn't who is going to report someone for a dog not being muzzled in their own home?
I also assume it's only when in public places because the UK has had muzzle laws (in public places) off and on since the major rabies scares in the 1800s iirc.