Twelve months ago, as a battle raged in Downing Street over whether to order a circuit-breaker lockdown, Prof Chris Whitty and Sir Patrick Vallance issued a stern public warning that England was headed for 200 deaths a day by November unless action was taken.

That was widely seen as a shocking and unacceptable figure. In the event, Boris Johnson finally caved in to the inevitable six weeks later, on 31 October, ordering a month-long lockdown.

When Whitty and Vallance gave that ominous press conference, daily deaths from the virus were running at fewer than 30.

As Johnson set out this year’s autumn and winter plan on Tuesday, the number of deaths had been consistently above 100 for more than three weeks, with little public outcry or political comment.

That public quiescence is part of the reason the government feels emboldened to press ahead with what it calls plan A – booster jabs for the over-50s, vaccinating 12- to 15-year-olds and advising the public to be cautious – rather than taking tougher action now.

Johnson acknowledged that measured on cases, hospitalisations and deaths, the situation is worse than in 2020; but insisted high vaccination rates meant the country was “incomparably better placed” to weather the winter ahead than it was last year.

Indeed, despite some of the alarming data, Johnson and his No 10 team remain relatively optimistic.

Their decision to press ahead with a “big bang” reopening back in July was widely viewed as a gamble – and derided as “reckless” by Labour – but cautious public behaviour helped contain the ensuing upsurge in cases to well below the 100,000 a day Sajid Javid had suggested was possible.

Johnson and other ministers now recite their favourite new attack line at every opportunity: “If it was up to Keir Starmer we’d still be in lockdown.”

That helps to explain why, as at so many other moments throughout the pandemic, instead of taking a precautionary approach, the government now prefers to hold tougher measures in reserve. As the prime minister put it: “We are now sticking with our strategy: in essence, we’re going to keep going.”

Downing Street insiders have also been buoyed up by advice suggesting that, with protection from the vaccine now high, modest changes well short of a lockdown could make a big difference – and by evidence that the savvy public adjusts their behaviour smartly when advised to do so.

Johnson’s deeply held scepticism about restrictions on daily life is also part of the picture. He is both ideologically wary of curbs on the public’s liberty, and – according to Dominic Cummings at least – even unconvinced of the evidence that lockdowns work.

Certainly, when asked about whether the government could reimpose working from home advice at Tuesday’s press conference, for example – one of the interventions suggested by Sage advisers – the prime minister warmly stressed the advantages of the return to the office and the “social capital” it brings. In his opening statement, he boasted that England now has “one of the most free societies and one of the most open economies in Europe”.

But as the document published alongside Tuesday’s announcement made clear, the government is well aware it may need to take action if the situation deteriorates – with the clinching factor, as last year, being whether the NHS risks being overwhelmed.

As well as setting out a smörgåsbord of contingency measures, including making masks mandatory and imposing compulsory vaccine passports, the autumn and winter plan repeatedly stresses the potential challenges ahead.

“There remains considerable uncertainty and scenarios which place the NHS under extreme and unsustainable pressure remain plausible,” it says at one point. At another: “The nature of the virus means it is not possible to give guarantees.”

It makes clear the criteria the government will use to make that decision, with hospital admissions the key metric alongside other measures including vaccine effectiveness and the link between hospitalisations and deaths.

All this makes it a blunter and more revealing document than plans the government has published at earlier stages of the crisis, suggesting thinking inside government has moved on significantly in the past 12 months.

Yet in other ways the dynamic remains strikingly reminiscent of a year ago, when Whitty and Vallance took to the airwaves: the experts warning of a rough winter ahead, and the prime minister clinging doggedly to plan A – for the time being at least.