NEW: Depsite push back from some in Shadow Cabinet, I’m told Lavery/Trickett/Murphy have successfully pushed back against efforts for Labour to back 2nd ref amendments on Saturday. Means Corbyn’s claim today that such matters were “for next week” remains position for now.
I also understand Jeremy Corbyn “promised” some leave-supporting Labour MPs that the whip would not be withdrawn in any circumstances on Saturday
However, the trade off appears to be a commitment to whip for a Kyle-Wilson style backbench amendment next week, assuming the PM loses MV4 on Saturday and has requested an A50 extension
Unsurprisingly, given the ruptures at the top of the party, some high level sources in the party who oppose JC’s position now pointing out all depends on exact nature of backbench amendments that might be put on Saturday, and that shadow cab decide whipping position not LOTO 🥶
Some who are pushing back on idea Labour will not back second ref amendment on Saturday are pointing to this comment in message JC sent to Labour MPs this afternoon: “we will look at the wording of any amendments on this carefully”. But timing is key - Saturday, or “next week”? 
