Why the letters are going in calling for May to go
If Tory MPs are right when they tell me that by lunchtime today there will be 48 letters of no-confidence in Theresa May lodged by them with Sir Graham Brady, chairman of the 1922 backbench committee, what does that actually mean?
Well, it is all about how they hate the Brexit plan she unveiled yesterday - or so I am told by rebel Brexiter MPs.
It is their “proof”, if such were needed, that May could not get her Brexit plan approved by Parliament in a “meaningful vote”. The logic is that if they are prepared to vote against her leadership of the party, they are obviously prepared to vote down the deal.
It does not, however, prove that May would be ousted if she ran in a subsequent leadership contest triggered by the letters. But that is irrelevant to them.
They say it would demonstrate beyond reasonable doubt that there are more than enough rebel Brexiter MPs - when allied with furious DUP and Labour - to rip up the terms she has negotiated for taking us out of the EU.
So they think she would be bonkers not to quit or drop her Brexit plan when their blocking minority is so publicly revealed.
We will see. She is a fighter, to put it mildly. The chairman of the party Brandon Lewis told me on my show last night that he would want her to stay and fight.
What is on public display is a Tory Party at war with itself beyond anything I’ve ever witnessed.
There is a residual chance that if she gives the performance of her life when selling the deal to the Commons today that some of the rebels could change their mind.
But I would not count on it.
This is how Jacob Rees-Mogg put it to me last night: “There comes a point at which the policy and the individual are so inextricably linked that that argument [against changing leaders] ceases to have any validity. I think we are coming very close to that point… We are not at that point… Well, let’s see what the Prime Minister says in her statement.”
Rees-Mogg added that if he puts in a letter calling for her to go - which I would be staggered if it is long away - he will not do it in secret like most of his colleagues but will make a public statement.