tl:dr; Opposition parties want to call an election as soon as possible, but want that election to happen as late as possible. An unconventional route – via a Vote of No Confidence tabled next week (9th September) – offers a route to this.

First of all: this is not my idea. It all stems from this tweet from Simon Banfield. All credit for the idea to him. I am just developing the idea a bit further.

So let’s get started. This is going to take a bit of explaining, but bear with me.

The quandary facing Labour, the Lib Dems and all other opposition parties in the House of Commons is not about whether a General Election is a viable way forward (there is a consensus that it is), but more a question of when it would take place. And coupled to that is the question of when the election would actually be called.

The Conservatives want a 15 October election – this just about plausibly allows them to say that they want a mandate to send Johnson to the European Council Summit on 17 October, abolish the backstop, and come back to the House of Commons with a Deal. Or, failing that, have time to vote in the Commons for No Deal, and leave on those terms on 31 October. Johnson has said categorically he does not want to extend Article 50.

The Conservatives could probably live with an election up until about 24 October – they would have to accept the extension from the European Council, but they can still then say OK, the first thing the Commons would do would then be to vote for No Deal so as to deliver exit on 31 October.

The opposition parties want pretty much the opposite – they want to make sure the Article 50 extension is watertight and assured, forcing Johnson to break the 31 October promise, and also to buy the UK some breathing space to find alternatives to No Deal. They would hence ideally like an election to happen after 31 October.

The problem for the opposition parties is the negative press coverage they get through delaying (like this in The Sun for example), and the accusation from Johnson in the House that Labour is dodging a General Election.

The ideal option then for the Labour Party would be to call the election early, and have the election late.

Here the government’s plan to prorogue Parliament is the problem. Prorogation can happen as early as the end of business on 9 September (Monday next week), and then only 25 working days have to pass before a General Election can take place. Call an election on 9 September… and you conveniently end up with the election on 15 October. Just as Johnson wants it.

The regular alternative would be to start the process on 14 October when Parliament returns after the prorogation, but that is more than 5 weeks away from now, and add the 25 working days, and you have an election on 19 November at the earliest.

Another possible problem is that both of these routes require a two-thirds majority under the Fixed-term Parliaments Act (FTPA).

An alternative that has been mooted would pass a Bill through Commons and Lords to make an exception to the FTPA, but here you need time in the Lords, and time is not what the government has enough of just now.

So here is the solution.

First, let the Benn Bill (against No Deal Brexit and proposing the extension) pass both houses – it ought to all be agreed on Monday.

Second, Corbyn should immediately table a Vote of No Confidence in Johnson’s Government. This needs only a simple majority under the FTPA.

Third, all opposition parties should then do nothing – and just sit out the 14 days foreseen in FTPA to try to find a new government that commands a majority. That takes you to Monday 23 September. After that the 25 working days to organise an election kick in, leaving you with an election day of 29 October. The new Commons takes a few days to be constituted, and needs a Queen’s Speech (more on this from Catherine Haddon here), so could get to No Deal Brexit only after 31 October. Safe.

But there are problems with this I hear you say.

Yes, indeed. Let me try to address them.

Could the Government cancel the prorogation?
Up until the prorogation begins it could, but that would be a win for the opposition – because they had argued prorogation was wrong anyway. So that’s a win for them.

Can the 14 days foreseen in FTPA and prorogation run in parallel?
I can find no reason to see why not, and FTPA states “days” and not sitting days or working days. And indeed the 14 days being during prorogation is perfect for this plan, as prorogation would prevent Parliament meeting to approve a new government.

What happens if the Government delays prorogation?
The Order stated that prorogation starts earliest 9 September, and latest 12 September. Johnson needs the 2/3 vote for a General Election on Monday 9th to get his election on 15 October (remember the 25 working days), so any small delay here only helps the opposition. And even if the VONC were voted on 9th, 10th, 11th or 12th September, the plan here still works.

What happens if Johnson simply ignores the Benn Law and does not ask for an Article 50 extension?
This would theoretically happen on 17 October, just a fortnight before the General Election. If the Prime Minister disobeyed the law passed by Parliament in the middle of an election campaign then that’s it for the Conservatives’ chances in the election. I cannot see how even Cummings would dare do this.

Is this not playing tricks with the Constitution?
You use the rules you have. Prorogation is not supposed to be used to prevent Parliament sitting for 5 weeks either. Given what has happened in the past month it would be hard for the Conservatives to bleat that some principle had been broken here.

Is there going to be even a simple majority in the Commons for this plan?
The Conservatives have been braying at Labour for the past 24 hours that Corbyn is running scared of a General Election. Were Tories to then not vote in favour in the Vote of No Confidence then they would rightly be accused of being hypocrites – the opposition would have given them a route to the General Election they wanted, and they would have turned it down. So this is a win either way for the opposition – get the majority and the plan happens. Fail and the Conservatives look like hypocrites.