Roger Ratcliffe has gained six months of time travel and has written back

16 September 2017. It is traditional to review a prime minister’s first 100 days in office after a general election. This time, though, it is hard to know how to begin the task of describing the whirlwind start to the government of shock winner Jeremy Corbyn.

It is worth recalling the phenomenal scale of the victory on that heady June day when Corbyn, flanked by close political allies Diane Abbott and John McDonnell, marched up Downing Street under a red flag. Just six weeks earlier, when the ex-Conservative leader Theresa May had called the election, Corbyn’s Labour Party was trailing by 18 points in opinion polls. As one commentator said, not even Lazarus could come back from such certain death. Experts predicted a Tory 100-plus majority, and post mortems are still going on to determine why May’s campaign crashed and burned.

The downward spiral began two weeks before 8 June, when Trust-me Theresa began to look like one of those posh women who get caught at supermarket self-checkouts with something very unexpected in the bagging area. Her pledge to rob some old folk of their winter fuel allowance and the forced U-turn on her so-called dementia tax led pundits to call the Tory manifesto the shortest suicide note in history. The end of free school dinners saw her portrayed as a present-day Mrs Bumble from Oliver Twist. To make matters worse, one long-serving Tory MP in an affluent Yorkshire constituency let slip that the party was actually planning a Northern Poorhouse.

With just a week to go a YouGov poll predicted a hung parliament, but even fake news in Conservative papers couldn’t halt the slide. The Telegraph reported that Corbyn would appoint Diane Abbott his Chancellor of the Exchequer in recognition of her hitherto unknown skill with numbers. And perhaps the most memorable headline of the election was the Daily Mail’s “Corbyn Plans Slaughter of First-born”. Yet so confident of victory were Labour that in the final days Abbott took to wearing an Afro wig dyed in the green, white and orange of the Irish tricolour.

The rumbles of shifting tectonic plates were audible on that bright Thursday in June when newly enfranchised 18 year olds and two million students uncharacteristically roused themselves and voted for Labour’s pledge to abolish tuition fees from September, saving themselves £40,000 worth of debt. The choice between parties was a no-brainer, they later told TV interviewers in café-bars across the country. As for old people, their horror at the Tories’ attack on pensioners’ benefits and assets made them stream to polling stations. The choice between parties was a piece of cake, they said at those day centres that had survived Tory cuts.

And so to that whirlwind first 100 days. Students and the elderly got quick rewards for their votes, while thousands of new nurses, doctors and policemen were recruited. Plans for a new nationalised rail network were published. Schools were properly financed. Private landlords were forced to lower rents. The biggest public house-building programme since the 1950s was announced. The bedroom tax and punitive benefits sanctions were scrapped. Disability benefits cuts were reversed. Libraries reopened. The Age of Austerity was over.

Across the country, even bin collections went back to weekly…

Roger Ratcliffe has worked as an investigative journalist with the Sunday Times Insight team and is the author of guidebooks to Leeds and Bradford. Follow him on Twitter @Ratcliffe