While most attention has understandably been focused on this evening’s main vote, a crucial sub-drama is playing out in the amendments which MPs will vote on first, assuming Bercow doesn’t go entirely rogue again. The two key amendments were Hilary Benn’s, which rejected both May’s deal and No Deal, and Tory MP Andrew Murrison’s, which insists on the Withdrawal Agreement being amended to specify that the backstop expires on 31 December 2021.

But Hilary Benn announced this morning that he was withdrawing his amendment, citing Bercow’s decision to alter Parliamentary procedure as one of the reasons his amendment was no longer necessary. The more immediate issue is that if his amendment narrowly passed, it would invalidate the subsequent meaningful vote, thus sparing the Government from a heavy defeat…

This leaves the Murrison amendment as the key one to watch. It has a weighty list of co-signatories, including Graham Brady, Damian Green and Rob Halfon, which strongly suggests Government support for the amendment. The Government may well accept the amendment in the hope that it limits the scale of their defeat on the meaningful vote tonight, then deal with the legal ramifications of it later…

UPDATE: Reportedly Business minister Claire Perry has been ringing round backbench colleagues pushing the Murrison amendment, suggesting at least an element of Number 10 co-ordination…