The rebel alliance has taken control of parliament – and Brexit. What happens next?

Every Monday, a group of unlikely bedfellows meet in Jeremy Corbyn’s parliamentary office. Jo Swinson, Liberal Democrat leader; Ian Blackford, the SNP’s Westminster leader; Caroline Lucas, the Green party’s sole MP; and Liz Saville Roberts from Plaid Cymru all gather to discuss their common aim — preventing a no-deal Brexit. This rebel alliance is more than just a group therapy session: last week, they succeeded in taking control of parliament and immediately started to give instructions to the Prime Minister. So their Monday club is now a kind of remote-control government, with plenty to discuss. While parliament is suspended, they’ve promised to keep in touch.

Corbyn usually kicks off proceedings with a broad-brush comment about the perils of leaving the EU without a deal. Seumas Milne, his strategist, then takes over to talk about the more technical side. They discuss matters of the week — legislation, whipping arrangements — and ways to be unhelpful to the Tory government generally. As the conversation goes on, talk may turn to the election they all know is coming. But it’s an uneasy conversation. Their party allegiances mean that in a snap poll they will be competing against one another. They share a common enemy. But beyond that: not so much.

It’s unusual. But so is much of what’s happening now in Westminster. We’ve seen a government lose its majority, but be denied a 15 October election by parliament. MPs have voted to give themselves power to instruct the government, issuing orders by passing laws. The fun was cut short by Boris Johnson’s decision to prorogue parliament, but still several MPs embarked on a 2 a.m. sing-off in protest. Even the prorogation is now in doubt after a Scottish appeals court this week deemed it unlawful. The case will now go to the supreme court.

Now the alliance have their sights on an early election, but on their terms. Johnson has repeatedly promised to leave the EU on 31 October, and they’ve ordered him to ask for an extension unless he gets a deal. They have brought six successive defeats on the Prime Minister and there are plans for more.

For his part, the Prime Minister has said he’ll just refuse to ask for this Brexit extension. But he has also said he will obey the law. If he can’t find a way to square the two, he could resign or be brought down in a confidence vote. Then the rebels would try to form a government whose sole purpose would be to write to the EU to ask for a Brexit extension. But after that, what would the rebels do?

As you might expect from a consortium of five rival political parties, there’s not much that they agree on. Corbyn once spent a Prime Minister’s Questions attacking Jo Swinson, rather than then Prime Minister Theresa May. The SNP intends to unseat Swinson at the next election. Should they be obliged to form a government, perhaps in the wake of a confidence vote, Jeremy Corbyn and his team believe he is the only acceptable caretaker prime minister, but Swinson has suggested she’d never put him into No. 10 even for a day. Corbyn would be a hard sell to anyone elected as a Tory MP.

So should Corbyn then step aside and make way for a less divisive interim leader? Labour fears that this would set a bad precedent for cross-party co-operation. Corbyn’s critics could suggest that, if he stepped aside for Brexit, he should do so again for government. And if Corbyn were to end up in No. 10 as a caretaker PM, it could be quite a bonus for the Labour party: who could now say it was unimaginable for him to take the job? ‘It would be a good showing, we’d just try not to nationalise anything for two weeks,’ jests a Labour source.

What every opposition party can agree on is that an election is coming — in which Labour could struggle to win a majority and may be on the hunt for partners. Electoral pacts are being discussed, but it’s proving challenging. Not everyone agreed on the election plan at first: Corbyn had wanted one straight away but was talked out of it by Keir Starmer, John McDonnell and Emily Thornberry. ‘Bad weather and bad turnout is worse for us than our opponents,’ says an unconvinced Labour source. ‘So waiting until November for an election is interesting.’

In the meantime, plans are afoot for a more radical Labour manifesto. In 2017, the party’s manifesto was surprisingly popular. There’s a view that the Conservatives have shifted towards Labour on domestic policy with the declaration that the era of austerity is over. In response, Labour figures believe they need to be even more radical. The latest idea, a right-to-buy for private rental tenants, is a taste of what might be to come. On Brexit, Corbyn is under pressure to move to an unashamedly pro-Remain position but his top team see a strength in maintaining some Brexit ambiguity.

Labour is, in theory, committed to fielding a candidate in every seat but, in some places, it might not try too hard. In the 2017 election, it ran a low-energy and low-finance campaign in Brighton Pavilion, which ended up returning Ms Lucas. This tactic might be repeated more widely and with more parties. So if Labour neglects a Tory/Lib Dem seat such as St Albans, then Swinson would promise not to worry too much about fighting a Tory/Labour marginal such as Bolton West. Both Labour and the Lib Dems think they can hurt the Tories more than each other. ‘I struggle to name you many Labour seats we think we could easily win,’ says a Lib Dem insider: Labour holds only seven of its top 50 targets.

The SNP is unlikely to be part of any pact: Nicola Sturgeon is hoping to win every seat in Scotland. The Conservative party is predicted heavy losses there while Labour is braced for a wipeout — not helped by John McDonnell and his support for a second independence referendum. When it comes to those rebel discussions on Brexit, the SNP tends to be kept at a distance. While they are an anti-Brexit party, their main agenda is a second Scottish independence referendum.

If Labour does manage to secure enough seats to be a minority government, the SNP (which might have 51 MPs) would be its most obvious partner. Swinson has ruled out a coalition with a Corbyn-led Labour and is on a mission to out-Remain the Labour party. At her party conference this week, MPs will vote on changing the party’s policy from a second referendum to full-on revocation of Article 50.

In the dog days of John Major’s government, there were plenty of meetings between Labour and the Liberal Democrats about a potential alliance. One was never needed. And it might not be this time. The Conservative path to a majority rests on the public now voting on a Leave/Remain axis rather than a left/right axis. Corbyn allies hope this calculation is wrong. Internal Labour party polling carried out in the Midlands and north of England into whether Brexit moves traditional voters to another party has been encouraging. They found that Labour-leaning Leave voters — nicknamed ‘Dennis Skinner voters’ — struggle with the idea of the Tories and see Johnson as no different to other Tory leaders.

But there is one group more easily turned by Brexit that could be decisive: non-voters, the ones credited for the shock Leave result. On the day of the EU referendum, Labour MPs say they began to get a sense that something was adrift when they saw people who lived in council estates with historically low turnout coming out to vote.

Current polling and prediction systems struggle to take this group in. There is a fear among the rebel alliance that Boris Johnson’s senior aide Dominic Cummings — the campaign director from Vote Leave — has managed to find a way to factor these voters in and is looking at very different electoral modelling to everyone else. That would explain why No. 10 is so bullish. The rebel alliance might be for nothing if it turns out it is fighting the wrong battle.