Well, this is literally going to cost the country billions of pounds. Perhaps trillions in the long term.
It is outrageous that fully comprehensive impact documents have not been done on such an important issue, that the process wasn't transparent, and fully published. It's indefensible, how can any of the Brexiters even defend it.
I work for the NHS as part of a decision making body, making decisions with potential impacts of millions of pounds, not billions (and nearly always geared to saving). Everything I do is published and subject to scrutiny. That's how its supposed to work in the public sector. But this government is committed to complete obfuscation, white washing, and blatantly ignoring experts because we've had enough of them. They've given up on evidence based policy, and consequently we are fucked.