I remember at work there was a guy who couldn’t attend a close because he had a wedding or something, but he assured us that everything would go fine, you just had to press a button on the spreadsheet and it would all be fine. I tested this in advance of close, as you do, and it failed completely. I left a few voicemails and was somewhat panicked.
He phoned in on the day of close, explained that he’d dropped a massive bollock, and there were a couple of major issues. With his guidance as to where the issues might be, I managed to fix it and everything was fine.
I am expecting this to be a poor analogy for Brexit.