As a Leave voter, it is satisfying to watch Boris's Johnson's bold Brexit plan unfold. The predictable backlash to it – what Jacob Rees-Mogg called the 'candyfloss of outrage' – is also an entertaining spectacle, with some of those most determined to stop Brexit resorting to ever lurid analogies to describe the Prime Minister. But why are the Government’s opponents now wailing so loudly? The answer is simple: because they know this week’s prorogation move has boxed them in.

First, let's be clear: whatever some of Boris Johnson's supporters might say, the plan to suspend Parliament is a deliberate attempt to decrease the parliamentary time MPs have to act to pass anti no-deal legislation. But the Government also showed that while it is willing to bend the rules it won't break them. 14 October was chosen as the end of the prorogation period (rather than the expected 9 October end of conference recess), because it is the latest date to comply with the terms of the Northern Ireland Executive (Formation etc) Act. This Act requires a report to be published on or before 9 October and then motions to be moved within both Houses within five days. Despite the extended prorogation period, the Government will be able to comply with this.

This makes it clear that the Government is working within the legal stipulations set by Dominic Grieve’s political chicanery, and is responding in kind. So there is nothing unconstitutional or improper here. And if the Commons does not like the move, then it is free to pass a motion of no confidence in the Government. As long as a majority of MPs have confidence in the Government, but disapprove of its Brexit policy, they cannot complain about any legal and constitutional means the Government employs to achieve its objectives.

Anti no-dealers are boxed in because it looks like they will be forced to use a vote of no confidence as part of their strategy (which, in any case, had always been their best bet). This fact stymies rebel Tories who are unwilling to lose the whip and end their careers in the party, and may keep the numbers in the Government’s favour. Legislative methods alone should now fail because of the time constraints and the tactics that the Government will no doubt use (Lords filibustering, for example) to delay if necessary.

Of course, if MPs are sufficiently united and determined enough, they can at the beginning of next week precipitate an early election. A Johnson-led Conservative party would go into this boosted by the perception of decisive leadership against those trying to thwart the referendum result. This is vital for the Tories if they wish to neutralise the threat from Nigel Farage and the Brexit party.

Yet a snap poll being called in the next few days is a less likely scenario. Instead, it seems more probable that we make it to the scheduled Queen’s Speech and EU Council summit on 17-18 October. Here Boris Johnson will hope to achieve a new deal, which seems to be the primary purpose of this move this week. As I wrote on Coffee House earlier this month, prorogation is the surest way to restart the negotiations, as there is no incentive for the EU to negotiate while there is a chance of MPs thwarting no-deal by legislation.

The question to ask then is what sort of deal is Boris Johnson aiming for? Does Downing Street simply want the backstop removed from the Withdrawal Agreement, or would it seek further changes as well?

Analysis of Dominic Cummings’s blog posts before he entered Downing Street gives us some clues. While he does not mention the Withdrawal Agreement explicitly or its details, there is a litany of remarks about the negotiations being poor.

Crucially on 27 March, he criticises those who supported the backstop for “effectively ending the ‘negotiations’”. This implies that his desire is more than removal of the backstop; otherwise surely there would be nothing further to negotiate. There is also another revealing passage at the end of the same post. In a section addressed to Vote Leave activists, Cummings writes:

“ Also, don’t worry about the so-called ‘permanent’ commitments this historically abysmal Cabinet are trying to make on our behalf. They are not ‘permanent’ and a serious government — one not cowed by officials and their bullshit ‘legal advice’ with which they have herded ministers like sheep — will dispense with these commitments and any domestic law enforcing them.

Cummings, of course, is now part of such a serious government. And what this passage means is that it is wrong to view any negotiations – and any resulting deal, before 31 October – as the end of the story.

At the minimum, the backstop must be removed, or we will leave with no deal. But if the EU offers nothing more, I think it is perfectly plausible that the Withdrawal Agreement without the backstop will be put to the Commons after the EU Council summit. Recalcitrant ERG MPs could then be brought to heel with the guarantee of a tough negotiating stance after we leave. This could include ripping up the very deal that had been agreed.

What is clear so far is that Cummings, Nikki da Costa (No.10's director of legislative affairs) and Rees-Mogg have played a brilliant opening salvo in the parliamentary battle. As I suggested might happen, those desperate to block Brexit were successfully lulled into thinking they had more time to act. And if Boris Johnson's opponents in Parliament really want to thwart his Brexit plan, they will have to avoid falling into the same trap again.