Oh I don't know, as far as I can tell / read the Irish government are YET to share arrivals passenger locator form data as collected at Dublin Airport / the ports etc with the British / N.I Govt about ANY arrivals that have taken place even from the start of the Pandemic never mind now. It's such a gaping hope in the fence and shows up the lack of cooperation on the matter that both parties are quietly treading around that fact without trying to bring too much (more) attention to it then there already has been. And of course without that data the British have no (easy) way of telling who is coming from where when they get off a flight or a boat from Northern Ireland to GB now.

https://www.irishtimes.com/news/poli...deal-1.4478584