Andy McDonald's resignation shows the left won't go quietly

Gulp. The most memorable moment for the woman who wants to be the next chancellor was meant to be her big speech today (more on that in a moment).

What she, and Labour's leadership hadn't bargained for was the angry departure of one of her colleagues from the shadow cabinet, which meant she, and several other colleagues, were sprung with it in the glare of the conference lights.

Mr McDonald didn't mince his words. The party is more divided than ever before, he alleged. Keir Starmer is not keeping the promises he made.

And he claimed the leadership had forbidden him from arguing for increasing the minimum wage to £15, something that he found intolerable.

He told me that he wasn't trying to cause trouble, that he had to make a stand on a point of principle. But some suspect sabotage from an old comrade of Jeremy Corbyn.

What on earth is really going on?

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Labour wanted today's focus to be on Rachel Reeves - her announcement of £28bn every year to help tackle climate change, her promise that Labour would take care with taxpayers' money, scrap business rates, and increase the tax on digital firms.

The details of her plans are not complete but the message she wanted you to hear is - Labour could be trusted with the public's money.

But Mr McDonald's departure is blatant evidence that there are more than just jitters inside Labour over the direction the party is taking.

One of his political pals, John McDonnell, used his resignation to suggest the conference is "falling apart".

Many members will push to approve a vote on Tuesday that includes a commitment to that much higher minimum wage that the leadership won't back, that could show the divisions very publicly. (Although it's worth noting that the leadership won't take a position on the policy either way when it comes to the vote, which is on a package of lots of different reforms.)

And Andy McDonald was cheered to the rafters at a left wing rally on Monday night, before Jeremy Corbyn himself appeared as the final starring act, with his customary standing ovation.

One supporter wore a Jeremy Corbyn mask while attending Labour's conference in Brighton.

The crowd might have been smaller than in previous years, but the passions are the same.

And the chants of "Andy, Andy" and "Oh Jeremy Corbyn" haven't gone.

Indeed some of Sir Keir's allies believe this resignation, dramatically timed during conference must be deliberately designed to distract from what the leader is trying to achieve.

It certainly is a distraction, and it certainly is divisive - but some close to the leader counter that it's a good thing that he's gone, despite the turmoil of the day.

Many of Sir Keir's supporters were spotted in the crush of conference jubilant last night - delighted that they had managed to get changes to the rules through, increasing their control of the party.

But Monday's events show that control is not yet complete. The left won't go quietly.

The plans the party wants you to see may be hard to hear above the noise.