Prince Philip's retirement is moment in British history

Prince Philip and the Queen arriving at Buckingham Palace. Credit: PA

The day began like few others.

It involved establishing - with some degree of urgency - that the Queen was still breathing.

And then establishing, with a similar degree of urgency, whether Australia and America were right or wrong to be speculating about the Duke of Edinburgh's health - or lack of it.

Pretty quickly, I was able to tell those who needed to know that the Monarch and her husband were alive and well and wrote a Facebook post accordingly - yet it was still not 6am.

But it left the next obvious question: what on earth was this announcement from Buckingham Palace which had got social media in parts of the world wrongly killing off one or other of the senior members of the Royal Family?

The royal couple on Buckingham Palace during the Queen's 90th birthday celebrations. Credit: PA

It wasn't an abdication, because we know the Queen's view on that (she won't).

It left a mixture of retirement, moving house (palace), Prince Harry's engagement or Kate's third baby.

So what to tell ITV's Good Morning Britain (in whose studio I now found myself sitting)?

Whilst we couldn't say what was due to be announced, it was important for us to say what wasn't.

In an age where many millions reach for their phone and social media as soon as they wake up, we had a responsibly to give some facts: namely that the Queen and Duke were still very much enjoying being the Queen and Duke.

And there this story had to be left for much of the next three hours.

Just a day before his retirement was announced Philip opened a new stand at Lord's cricket ground. Credit: PA

Not until the staff of the Royal household had been told at 10am, would Buckingham Palace release a statement to the rest of the world.

Staff were bussed in from Windsor.

And a simultaneous announcement was made to those who work in other royal residences like Sandringham and Balmoral.

When, minutes later, the news arrived of the Duke's retirement, you could feel - among the amassed crowds of worldwide TV crews and reporters - a collective sense of relief.

Relief the Duke was still breathing. Relief, too, the news wasn't so big that they were about to lose the next fortnight of their lives.

And with that confirmation of Prince Philip's retirement in August (two months after his 96 birthday) it became a good moment to work out why we care.

Philip recently presented singer Kylie with an award at Windsor Castle. Credit: PA

The Queen might be the longest serving Monarch in British history but the Duke of Edinburgh has also earned his place Britain's longest reigning consort.

He has been in the public eye and part of our national life for seven decades.

A man who modernised the royal family, established the Duke of Edinburgh Award scheme, gave a high profile to hundreds of charities, made people laugh, made people cringe, but above all gave everything he had to supporting his wife, The Queen.

We know he gave up his navy career for her, we know he walked a few paces behind her wherever they went, we know he could be blunt and, at times, brutally honest.

A young Prince Charles and sister Princess Anne with their parents in the Fifties. Credit: PA Archive

But has any of us ever considered what it must have been like to spend the greatest part of your life in the Queen's shadow?

Because this is no ordinary marriage. No ordinary family.

The Queen's first priority was always her country and her job as Head of State.

Most people who know the Queen will acknowledge motherhood came second. And so too her marriage.

But despite it all, the Duke has chosen to keep working, to keep up the royal engagement and to keep serving his wife well into his mid-nineties.

Most of us, remember, retire in our mid-sixties.

The royals raise a glass at the Queen's birthday party in 2015. Credit: PA

No one can pretend that his life has been anything other than privileged. And of course he's never had to struggle to put food on the table.

But it's worth considering what he's given in return: 70 years of service to the Monarchy in his adopted country.

And this is now a significant moment of transition.

I'm sure we will continue to see the Duke after his retirement.

I suspect there will be balcony appearances every so often at Buckingham Palace.

And I can't see why he'd want to stop going to the Cenotaph for the Service of Remembrance each year.

The Queen will continue her duties alone or with younger members of the royal family. Credit: PA

But the Queen will, from the Autumn, start doing more visits on her own or with another member of the Royal Family.

She'll keep working - she's younger (albeit 91) and will remain the Sovereign.

But we have just witnessed a moment in British history.

And this particular chapter will close when the Duke of Edinburgh's royal diary becomes permanently empty at the end of the summer.