GDP was down 2.9% in January as the supply chains have been thrown into havoc and business disruptions have been described as "endemic," and it turns out the
government didn't do an economic assessment on the trade deal despite it being the most consequential trade agreement in memory. It's one thing to have the economy torpedoed by global macro economic conditions, it's an entirely different one to steer the ship headlong into the iceberg as Britain has done.
I think no one really expected that Brexit would be any good idea for UK. The long term effects are definitely going to be negative. So far the financial services have been excluded from the withdrawal agreement, but eventually there needs to be a new regulation in place. I don't think the EU will allow to keep up the dependency on London for all the trading and clearing in Euro. Amsterdam might be a big winner here, but I would expect that France wants a share as well, and probably so wants Germany. Maybe a split between Amsterdam, Brussel, Paris and Frankfurt would be possible.