On a cynical note, why should UK worry about the falling pound as a result of Brexit?
It will help exporters, incoming tourists, and overseas investors surely?
Just keep this thing on a low burner, and all the trade deals will be a doddle when the pound goes lower again due to the uncertainty.
But unfortunately it will be a disaster for those ex pats living abroad on fixed sterling pensions for example, but who cares about them lol, and imports to the UK aswell.
No bother so, keep on trucking.