If you were you wouldn't have left the EU. Talk is cheap.

Huh? OK. Indeed. Talk is cheap and is not worth running in circles here.

It ignores reality though. The UK’s only land border is completely open and in many cases undefined because the border commission of 1921 never completed its work. And at any attempt to digitize that border and they will literally blow it up.

There is no requirement for a British or Irish citizen to even own a passport to travel or work in the British Isles. Neither country has a clue as to how many citizens change residence in a given year.

Perhaps a good idea to get back to OP no?