Here, then, are some of the key points that have forever changed our understanding of how Elizabeth’s record-breaking reign finally drew to a close – and the challenges facing her son and heir King Charles III as he navigates a new and very different landscape.

The Queen remained dutiful right until the end

When Sir Edward Young, the Queen’s private secretary, opened the last red box that had gone to her, he found the long-list of candidates for the Order of Merit, with her choices ticked.

On September 7, the day before she died, she spent the day in bed at Balmoral yet still made plans to participate remotely in the scheduled Privy Council meeting – plans which had to be cancelled at the last moment.

The Queen is pictured meeting the new Prime Miniser at Balmoral. Her Majesty passed away two days later

Sir Edward Young, the Queen’s private secretary, opened the last red box that had gone to her

The Queen had spent the day in bed at Balmoral but still planned to participate remotely in a scheduled Privy Council meeting

The incredible revelations were from Robert Hardman’s new book is called Charles III The Inside Story

She had completed the task just two days prior to her death, with Hardman writing: ‘Even on her deathbed, there had been work to do. And she had done it.’

She knew her health was failing

The Queen suffered ‘multiple’ health conditions in her final year and was well aware she wouldn’t reach the age of 100 as her mother had.

Plans were drawn up for a Regency

Aides prepared for the Queen suffering a slow deterioration or a ‘sudden public collapse’ in her final years with secret plans for Prince Charles to become regent. Options varied from a ‘regency light’, with minimal involvement by Charles, or a ‘reversible regency’ in which he would discharge her duties during a period of her incapacity.

Charles and Camilla spent an hour with her privately

After flying by helicopter to Birkhall, their home on the Balmoral estate, Prince Charles drove the couple to Balmoral castle in a borrowed Land Rover.

They were greeted by Princess Anne, who had happened to be staying, who led them immediately to the Queen’s bedside to spend time with her.

Charles told both his sons to travel to Balmoral urgently to say their goodbyes

The Royal Air Force arranged for Prince William to fly with his uncles from RAF Northolt to Aberdeen at 2.30pm.

Prince Harry, who happened to be in London with Meghan for a few days of charity engagements, chartered his own plane to Aberdeen.

Aides discussed plans for Prince Charles to become regent if the Queen’s health deteriorated

Charles and Camilla at Birkhall, their home on the Balmoral estate

Princess Anne had been staying with her mother, the Queen, and greeted Prince Charles and Camilla as they arrived to say their goodbyes

Prince William drove his uncles and Sophie from Aberdeen airport to Balmoral

Prince Harry arrived to late after chartering his own plane

Catherine, Princess of Wales decided not to attend

In his memoir Spare, Harry writes of feeling deeply offended when his father asked him not to bring Meghan with him to Balmoral. Learning that Kate would not be there either assuaged his anger – but Hardman writes that he did not realise she hadn’t been asked to stay away.

In fact, she had decided she should remain at home for the sake of her children, who were starting a new school, Lambrook.

William was still angry at Harry’s ‘reckless betrayal’

Harry claimed in Spare that he had texted his brother to ask about his travel arrangements, but not received a reply.

Hardman writes: ‘Clearly, Prince William did not regard this as the appropriate moment for the intensely difficult conversation he needed to have with his brother’, alluding to William’s anger over the Sussexes’ ‘reckless betrayal’ during their Oprah Winfrey interview.

This was the broadcast in which they claimed Kate had made Meghan cry during a row over a bridesmaid’s dress, and that two members of the royal family had expressed concern over the colour of then-unborn Prince Archie’s skin.

There was also wariness about Spare, which had not yet been published. ‘Some of the family were probably ready to give him a piece of their mind,’ Hardman quotes a source saying.

The Queen ‘slipped away’ in her sleep

According to a memo written by Sir Edward Young to record the momentous events for posterity, which now resides in the Royal Archives, the Queen ‘slipped away’ peacefully in her sleep, without any pain.

Charles learned the news of the Queen’s death when he was addressed as ‘Your Majesty’

Not expecting his mother to die quite so soon, Charles had been out gathering mushrooms in the grounds at Birkhall when he received a call from his sister, the Princess Royal, telling him to come immediately.

He and Camilla jumped back into the Land Rover, but hadn’t yet arrived when Sir Edward called to tell him that the Queen had passed away. ‘He had just turned off the B976 onto the back drive of the estate when, at the age of 73, he was addressed as ‘Your Majesty’ for the first time,’ writes Hardman. ‘No further explanation was needed.’

There was a certain amount of wariness regarding Harry as Spare was yet to be published

The Duke of Sussex at Aberdeen Airport as he travelled back to London following the death of his grandmother, Queen Elizabeth II

The organisers found that ‘everything that could go wrong did go wrong’

The whole parade was ‘out of step from the start’ after the bagpipes pre-empted the first command – but only at the rehearsal, fortunately!

Harry did not eat with Charles, William that night

Prince Harry did not make it to Balmoral in time to see his grandmother before her death.

He said in Spare that he was informed that she had died via an alert from BBC News on his phone – although Hardman suggests that several attempts had been made by King Charles to call him with the news, which were unsuccessful because he was airborne at the time.

Harry dined alone that night, while the King had dinner with William and Camilla.

‘The King needed to have vital but discreet discussions with his elder son,’ writes Hardman. ‘In years gone by, such a moment would automatically have included his younger son. But not any more.’

The funeral procession risked disaster

The late Queen’s funeral rehearsal was a ‘comedy of errors’ as organisers found that ‘everything that could go wrong did go wrong’.

The carefully calculated parade times had failed to take into account the different length and speed of steps required by a Guardsman and a Royal Navy recruit carrying a two-ton gun carriage, meaning the front of the parade ‘ended up parting company with the coffin.’

The whole parade was ‘out of step from the start’ after the bagpipes pre-empted the first command. One band had been led to the wrong start point. And one Gentlemen at Arms was nearly crushed between the gun carriage and Wellington Arch after going the wrong way.

Prince William was furious over Harry’s ‘blatant attack’ against Kate in his Netflix documentary

The Duke of Sussex claimed that for male members of the royal family, ‘there can be a temptation or an urge to marry someone who would fit the mould – as opposed to somebody who you perhaps are destined to be with.’

William saw the comments as clearly about his wife Kate and regarded them as ‘the lowest of the low’.

Prince Harry claimed in the programme that for male members ‘there canbe the temptation to marry someone to fit the mold’

William saw the comments as clearly about his wife and regarded them as ‘the lowest of the low’. The Prince and Princess of Wales and the Duke and Duchess of Sussex make a rare joint appearance to see flowers and tributes to the late Queen at Windsor

Queen Camilla’s family call her Lorraine

Once, there seemed to be no chance of Camilla ever becoming Queen, due to public antipathy towards her for her role in the breakdown of Charles’ marriage to Diana.

It was during that period that her family gave her the humorous nickname ‘Lorraine’ – as in the French la reine, meaning Queen. ‘She always saw the funny side of that – even if Prince Charles did not,’ says a friend.

The temperature has dropped even further at the royal palaces

Not only does the King not switch on the heating during the winter to avoid contributing to climate change, but he is also a ‘compulsive window-opener,’ according to Hardman.

‘There’s a constant battle about it,’ says Camilla’s sister Annabel Elliot. ‘He will have opened it. She will creep in behind and shut it. So there’s a lot of “Oh darling, you shut the window.”

“Yes, I have, because we’re all freezing.”’

Prince William might not head the Anglican Church

While the Prince of Wales admires and respects the Church, and enjoys attending services at significant times of the year, such as Christmas and Easter.

He feels he is no different to the average Briton in that he is not a regular worshipper.

And that has led to speculation as to whether he may consider not taking on the formal role as head of the Church of England – that British monarchs have held since the time of Henry VIII.

Mrs Annabel Elliot in interview for Charles III revealed Queen Camilla’s nick name

Annabel giving a small wave during her sister’s Coronation in May last year

Prince William is not a regular worshipper but attends services at significant times of the year

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