There will not I think be any evening of television hosted by Jools Holland, with streamers, fizz and jazz bands, on the 31st January to mark our departure from the EU. There will, though, I strongly suspect, be lots of firework displays, which will pose the police with an interesting problem.
The current firework laws allow fireworks only until 11pm other than on Guy Fawkes night, Diwali, Chinese New Year and Christian new year. One of the quirks of the WA is that it specifies midnight on the 31st CET as the exact moment of the UK's departure - 11pm UK time. Technically, fireworks ignited before the hour are quite legal, those exploded after could earn a visit from Plod.
I don't think this will be an issue anywhere outside the most remainery parts of London, in which the victims of Brexit Derangement Syndrome will deluge the Met with phone calls, tweets and emails complaining about the fireworks. Brexiteers will take a delight I suspect in guerrilla celebrating - sneaking into closed parks and onto open spaces to set off half a dozen rockets after 11pm, then flee. One can understand and sympathise with such actions, and we could see the skies of the whole of Britain (even Scotland had a substantial Leave minority) lit up in a coruscating display of sound and light.
What we will not hear, it appears, are the bongs of Big Ben. This, I think, is probably right. TPTB have invented a theoretical cost of half a million to ring the bells and that's enough to kill the idea. It is not a good look for any official bodies to appear triumphalist about leaving; our national and state institutions belong just as much to remainers as they do to leavers, and it really wouldn't be right to use them to crow. The fireworks and private celebrations will be quite enough.