There's just one big story in town: the shock resignation of Ivan Rogers, the UK's ambassador to the EU. It means that when Britain's exit talks start, not a single senior figure, on the civil service or the political figure, will have recent experience of negotiating at a European level.

(Just David Davis, who was Europe minister from 1994 to 1997, has done it before. Back then, the EU had just 14 members excluding the UK. It now has 27.)

"Brexit talks in chaos" is the i's splash. "Brexit row as top EU envoy stands down" is the Guardian's. To make matters worse for the government, Rogers' email announcing his decision to step down has leaked to the Times and the BBC.

The email is littered with what are widely being described as "coded" criticisms of the PM and her senior team, but you don't need to be Alan Turing to crack this one.

"Contrary to the beliefs of some, free trade does not just happen when it is not thwarted by authorities" - a strike at Liam Fox. "I hope you will continue to challenge ill-founded arguments and muddled thinking" - a strike at basically everybody in the government. Plus a final aside on the need to "deliver messages that are disagreeable to those who need to hear them" - a strike at Theresa May, but also, I'm told, at those former aides to David Cameron who have widely briefed that Rogers' caution meant that Cameron settled for a worse deal than he could otherwise have got in his ill-fated renegotiation.

Does it matter? The Institute for Government's Jill Rutter sets out what it means for Whitehall in a handy explainer. The lowdown: the best of all possible worlds would have involved Rogers extending his stay past his October 2017 leaving date, but, on the whole, it's better to have his replacement in post sooner rather than midway through the exit talks.

But that Rogers, instead of extending his tenure, is leaving early attests to that other growing fear about Britain's Brexit talks - that May exiles those who disagree with her to the outer darkness and that Britain's exit strategy is being planned by yes men and boundless optimists.

For Brexiteer ultras, his departure is only good news. They feel that Rogers was a roadblock to Britain getting the best possible Brexit, and that his belief that a post-Brexit deal could take up to a decade was the sign that his heart wasn't in it.

They'll be delighted with the frontpage of today's Telegraph: "May to pick Brexiteer as our man in Brussels" is their splash. The plan is to secure someone who "believes in Brexit" - not someone like Rogers, who warned that a full deal with the EU27 could take up to a decade.

There's a lot to unpick here, so I will try to keep it brief: firstly, one of the good things about Britain is that we don't appoint civil servants based upon whether they believe in government policy. Secondly, the Brexiteers seem to believe both that the EU is a dysfunctional mess that can't strike a trade deal to save its life and also that a quick and successful Brexit deal can be struck in two years. This is somewhat odd, to put it mildly.

But thirdly and most importantly, what really matters, as Rogers himself says in his parting message “serious multilateral negotiating experience is in short supply in Whitehall, and that is not the case in the Commission or in the Council”. The priority if May really wants to make a success out of Brexit isn’t getting an ambassador who believes in Brexit – but one who knows what they’re doing.