Ah I dunno
the logistics of the whole thing are insane to me, it will take years, can't see it happening in the next decade anyway. There are also a lot of reservations down south about our ability to "absorb" the North given their reliance on Westminster for so much funding. There would have to be a very, very long bedding in period where the UK still support NI. Also, a lot of Catholics have historically rejected unification too because the NHS is a much better health service than the HSE, they have jobs with the UK Civil service etc. so it's not simple for them either. It's a mouth wateringly huge undertaking if it does happen so, hopefully, unlike this thread's namesake, it's done slowly and carefully. It'll happen but it could take a long time.