Or they pick the third option. They keep the northern Irish open, and simply deport all non Irish without proper documentation. If course the EU won't allow a

Or they pick the third option. They keep the northern Irish open, and simply deport all non Irish without proper documentation. If course the EU won't allow a backdoor into the common market, so they will be the ones pressuring Ireland for a hard border. Whatever hard border would be imposed solely by the Irish republic, which means the British government abides by the good Friday agreement.