Will the UK have left the EU by October 31st? At the Conservative party conference, ministers, MPs and activists are keen to repeat the event slogan: ‘Get Brexit done’. However, many are unsure as to when exactly Brexit will get done. Johnson has promised to take the UK out of the EU by 31 October “do or die” – he has repeatedly said “extension means extinction” for the Tories. But with parliament passing legislation to try to force him to seek an extension, and opposition MPs refusing him an election until that extension is secured, senior Conservatives are starting to contemplate a world in which Brexit isn’t done at the end of October.

Whether a deal is on the cards will be known in the near future as Downing Street prepares to unveil its offer to Brussels. However, ministers and MPs see agreeing a deal with the EU as unlikely. “I give it a one in three chance,” says a government minister keen for a Brexit deal. Even Johnson, normally the biggest optimist in the room, is viewed to be relatively downbeat about the chances by members of his cabinet – with the prime minister playing down the chances of a deal during a cabinet conference call last week.

What’s more, Conservative MPs who represent marginal Brexit-backing seats worry that an attempt to pass a Brexit deal in the next few weeks could backfire on them at the ballot box. While Tory MPs believe that recent rhetoric from No 10 about the Benn bill being the “surrender bill” has cut through with leave voters, they worry that an attempt to pass a deal similar to the withdrawal agreement could backfire. The Tory worry is that Johnson will go all out to sell a small change to the withdrawal agreement as a big win and then fail to get it through parliament. “We’d go into the election with Nigel Farage able to say we were no better than Theresa May and her withdrawal agreement,” one MP in a leave seat says. “He could cry Brexit betrayal.”

Many MPs hope Johnson’s manoeuvring will be enough to simply ensure the UK leaves on the 31 October – deal or no deal. At that point, MPs would likely bring the government down and an election would follow in which Johnson had made good on his promise.

Despite this prevailing mood, some senior government figures urge caution. While a handful of No 10 aides – headed by Dominic Cummings – have suggested they have a way around the bill, which would means Johnson would be able to refuse to request an article 50 extension and not be in breach of the law. The apparent loophole is reportedly known only to Johnson’s inner circle. However, as I write in the Guardian, few believe that it is a cast iron reliable route. Instead, it’s about the narrative and the fight.

Cummings has told colleagues that he expects the last two weeks of October to be spent in the courts. Whatever trick Johnson’s senior aides have up their sleeve, expect it to be contested – and Johnson to potentially be defeated in court again. “It’s about showing that we have done everything possible to try to meet that deadline,” says one government aide. “Hopefully it will work but if it doesn’t the public will know it was the Tories who were the ones trying to make it happen.”

Were the courts to legally force Johnson to request an extension, he would be faced with a choice: request or resign. Within No 10 there is mixed opinion on the pros and cons of resigning – Johnson is personally against the idea. What they agree on is that however they play it, any extension will not be their fault.

If it’s ordered by the courts, blame could be pointed at judges rather than ministers. One source of encouragement is recent focus groups where attendees spoke about the courts getting involved with politics. Attendees saw judges as part of a more general theme of everyone trying to stop Brexit – and identified Johnson as the person trying to deliver it.

An election after an extension has been agreed would no doubt be difficult for the Tories. It would risk disillusioned Brexit voters moving to Farage’s party – and leave voters concluding that Johnson was ineffective. But increasingly, Tories believe that if they absolutely had to, they could wear it.