Disbelief and dejection were the overriding emotions in the predominantly anti-Brexit City of London when news spread of the UK’s vote to split from the European trading bloc. The referendum in 2016 would force UK policymakers' to unpick some 40 years of regulation, financial titans to rethink their London-centric European business models, and thousands of European financial professionals to question their loyalties.

Five years on, and the true implications of the UK’s vote for Brexit are only just becoming clear.