Well, it looks like it is all up for Corbyn.
The whole Shadow Cabinet are reportedly set to walk out, even the ones who didn't want him to quit. They recognise he can't survive the sort of damage the Benn-Bliar wing are intent on inflicting.
Which is a fucking shame as it shows the Labour Party have learned nothing rom 2010, the SNP overthrowing them in Scotland, 2015, Corbyn's election, or the Brexit referendum. They have not got clue what their membership wants, far less the general population of Britain.
EDIT - Well, the hammer seems not to have fallen yet. A lot of fighting talk from Corbyn's team, and only the one resignation so far. A lot of bitter sniping from back benchers like Chris Leslie. Interestingly, Hilary Benn refused to say how many resignation he was expecting to happen. Maybe he's not as sure of his support as he was 24 hours ago. Maybe those late night calls went unanswered.