Gideon Rachman in The Financial Times on why Brexit may not happen.

And what kind of new concession should be offered? That is easy. What Mr Johnson would need to win a second referendum is an emergency brake on free movement of people, allowing the UK to limit the number of EU nationals moving to Britain if it has surged beyond a certain level.

In retrospect, it was a big mistake on the part of the EU not to give Mr Cameron exactly this concession in his renegotiation of the UK’s terms of membership early this year. It was the prime minister’s inability to promise that Britain could set an upper limit on immigration that probably ultimately lost him the vote.

Sounds logical to me.