The wider context of this, which I still don't think is being given enough attention, is the rapidly closing window for Financial Services firms to decide their Brexit strategy.

The window is closing because of the time - 12 months - that regulators will need to process applications for any change of status (e.g. from branch to subsidiary). This is clear but implicit in the PRA CEO's recent letter to firms, requiring them to set out their strategies by July.

Working back from March 2019 - in the current absence of any agreed transition period, mutual recognition of standards etc. - this doesn't give the politicians much negotiating time! 

Ideally, firms may want to see how these negotiations pan out but the regulators, given their remits, can't afford to wait. 

As a result, firms who haven't already decided will need to settle quickly and clinically on their best option, given the uncertainty, and then manage the execution risk through what could well be a difficult period.