Robert Peston: Is PM bluffing when he says he'll pull Brexit bill rather than accept delay?
Labour whips asked the government for eight days of debate for the Withdrawal Agreement Bill, which would mean the bill would not become law - if it did - till the middle of November.
Which is well passed Johnson's October 31 deadline.
And Tory whips have said no, nay, never.
Or so I am told.
What is more, Brexit Secretary Stephen Barclay has been telling MPs in private meetings that if the government loses the vote tonight on the so-called programme motion, which sets the timetable for the bill to become law before October 31, then the bill will be killed and there'll be a general election.
As it happens, I don't think it will be quite as straightforward as that.
Just as soon as the PM were to lose the vote on the timetable, he would ask for a statement from EU leaders that there'll be no delay to Brexit beyond October 31 - in the hope that would focus the minds of MPs that the price of their desire for more scrutiny of the 100 page bill would be a no-deal Brexit.
Johnson is not so naive as to expect the EU to set the October 31 as a hard, immovable deadline. They'll probably offer the delay that Parliament forced the PM to request, against his will, till January 31, or thereabouts.
At which point Johnson will try to get the general election he's long sought - which he'll obtain so long as the SNP holds to its commitment for an early election.
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So Tory AND Labour MPs who want Brexit, but hate how little time they've been given to debate the Brexit legislation, face a tricky judgement.
Do they really believe Johnson will pull the Brexit bill rather than break his promise to deliver Brexit on 31 October?
I have spoken to many of these MPs estranged from both Johnson and Corbyn, from both parties, and they simply can't decide whether to call Johnson's bluff and demand a longer legislative timetable.
The vote on the programme or timetable motion will be very, very tight.