As Boris Johnson made a last minute appeal to grumpy backbenchers in a wood-panelled Westminster committee room late on Tuesday, journalists listening outside heard a noisy round of desk-banging, in what sounded like a show of support for the embattled prime minister.

Yet little more than an hour later, the idea he had rallied MPs behind him was exposed as a sham, as 100 Conservatives trooped through the “no” lobby, to oppose Covid passes – a measure he had insisted was essential to tackling the pandemic.

“It was so stage managed,” complained one rebel, of the hastily convened meeting meant to win them over to Johnson’s cause. Hand-picked loyalists hammered on the desks and asked supportive questions, they said, adding that it was like something out of the court of Kim Il Sung, the founder of North Korea.

The prime minister brushed off “partygate”, urging colleagues, “don’t believe what you read in the papers”. But MPs say the scale of the rebellion was so great partly because they wanted to express their exasperation about what they see as Downing Street’s botched handling of the string of negative news stories about lockdown-busting gatherings.

When the result of the vote on Covid passes was announced, Johnson’s aides were taken aback – the rebellion was the second largest suffered by a Conservative prime minister, beaten only by Theresa May’s first attempt to get her Brexit deal through parliament.

Back then, Johnson himself was among the rebels, as he urged May to “chuck Chequers,”, a reference to where the deal was hammered out. It helped to fatally undermine her and pave the way for his own arrival in Number 10.

Less than three years on, it is Johnson’s authority that appears shattered after a series of missteps – from his rambling levelling up speech, to questions about the funding of his lavish refurbishment of the Number 11 flat.

Pictures of Johnson on Tuesday showed him looking tired and disconsolate.

One former minister traced the crisis back to the abortive attempt to prevent disgraced MP Owen Paterson from being punished for paid lobbying. “The PM has not been forgiven for the Paterson affair, waves of retribution are hitting as a result,” they said.

Jostling among the allies of potential leadership contenders is intensifying. Teams are “actively recruiting” in a more “blatant” way, according to one MP. Others said they have been sounded out and asked how they would vote in a future leadership contest, potentially in the spring.

Supporters of Nadhim Zahawi have been touting him as a future prime minister, while Liz Truss has been entertaining groups of backbenchers. She regularly tops the cabinet league table published by the Conservative Home website, based on the views of grassroots Tory members. In their last poll, Johnson came 30th.

With MPs now leaving Westminster for the festive recess, Downing Street sources concede their sole aim at this point is to get through to Christmas without any further major setbacks.

A No 10 insider said Johnson’s advisers were “panicked, stressed and on a different planet,” and the operation in Downing Street was “falling apart”.

Johnson is under pressure from colleagues to shake up his team, to improve relations with backbenchers and avoid repeated misjudgments. But senior Conservatives question who would take on the job – and whether Johnson would be willing to listen to them.

One source claimed the prime minister had recently sought to persuade his former chief of staff Lord Eddie Lister to come back into Downing Street – but that Lister wasn’t keen on working alongside his successor, Dan Rosenfield.

Reports that David Canzini, a colleague of Australian election strategist Lynton Crosby, could be brought in at the behest of rightwing backbenchers, have been denied by No 10.

As the transport secretary, Grant Shapps, made clear during interviews on Wednesday morning, the hope in Downing Street is now that with “plan B” restrictions in place and the revved up booster drive, they can avoid being forced into taking more emergency Covid measures this side of the festive season.

Shapps said he believed “with some confidence,” that no new measures would be needed before Christmas – though Whitehall insiders concede the situation is fast moving.

Number 10 insiders took some solace from the response to Johnson’s televised appeal to the nation on Sunday evening. The Covid Recovery Group chair, Mark Harper, has accused the prime minister of “scaring people witless”, with his warning of an Omicron emergency.

Boris Johnson addresses the nation on Sunday evening.

But the next morning, queues outside vaccine centres were noticeably longer, as members of the public responded to the call to get their third jab.

“It was a real step-change,” said one Number 10 insider, suggesting that it cut against the idea that Johnson’s authority is so shattered the public will no longer give him a hearing on public health issues.

They said the booster “mission” was now Johnson’s primary focus, with the prime minister spending much of his time on it.

Some of his backbenchers were also encouraged by Johnson’s performance at prime minister’s questions on Wednesday, at which he appeared less at the mercy of events than at last week’s disastrous outing.

“I thought he gave Keir Starmer a good run for his money,” said one supportive backbencher, who had voted against the government on Tuesday evening.

But while Johnson may be keen to batten down the hatches for the festive period, he faces at least three more severe challenges in the coming days.

In the early hours of Friday morning, all eyes will be on North Shropshire, where the Conservatives are warning they may not manage to hang on in Paterson’s former seat, which should be ultra-safe.

And the coming days should also bring cabinet secretary Simon Case’s report into a string of alleged parties in Downing Street; and ethics adviser Lord Geidt’s response to discrepancies between what Johnson told him about the flat refurbishment, and what the Electoral Commission revealed.

Some MPs say they are waiting on the Geidt and Case inquiries before seriously considering putting in a letter to the 1922 Committee chair. It would take 54 such letters to trigger a vote of no confidence in Johnson – though even then, he could conceivably still win it.

Others say they are willing to give him the benefit of the doubt until the new year, in the hope that he can overhaul his team, sharpen up his act, and give his flailing government a clear set of directions, by spelling out what “levelling up” really means.

Despite anger against Johnson being at record levels, a former minister cautioned not to write him off yet. “He’s completely Teflon. If anyone can get through this, it’s him.”