Just in case you are keeping count, it was exactly 40 days after their $50 million wedding in 2011 that newlyweds William and Kate the Duke and Duchess of Cambridge stepped out for their first glitzy evening engagement as a married couple. For the historic moment, the newly-created duchess opted for a pink, crystal-covered Jenny Packham frock that was exquisitely princess-y (Cinderella, eat your heart out).
In the years since, when it comes to night-time events, she has experimented with sweetheart necklines, ruching, lace, one-shouldered draped numbers, and even some misjudged sequins. It's been a whirlwind ride. Not.
Which is why, with the benefit of hindsight, the outfit that Meghan Markle chose in February 2018, three months before her wedding, for her first official night-time engagement should have served as a big red warning sign about the tumult that was to come.
On that blustery London night, the then 36-year-old attended the Endeavour Awards with her fiance, braving some particularly on brand bad British weather for the event.
So, did she roll up wearing a Kate-esque dress, all glitz and sparks?
Instead the now-Duchess of Sussex wore an impossibly chic tuxedo from Alexander McQueen with a Prada clutch and Manolo Blahnik heels.
At the time, the UK press hailed the look: The Daily Mail ran the headline, "Royalty suits her!"; the Express said she "stunned" on the night and the Mirror lauded her "glamorous" ensemble.
And, any fashionista worth their old Celine will tell you, Meghan looked downright sensational.
However it retrospect her choice of look should have set off alarm bells in Buckingham Palace.
If ever there was a moment that symbolised her intention to do things her own way, it was this ensemble.
Women might have been publicly wearing slacks in the UK for 140 years but in the confines of the royal family, they only rarely make their way into royal style rota.
The house of Windsor might these days be on Twitter and Instagram, embracing the power of social media with all the enthusiasm of a minor Kardashian but in many respects the 21st century seems to have failed to breach the palace gates.
During the family's annual summer holiday in Scotland (any oxymoron if ever there was one) the family is still woken by a traditional piper every morning, no lie-ins allowed. For one HRH to speak to another still involves both parties' private secretaries and the detailed diary co-ordination.
Never one to let modernity have its way with centuries-old customs, Queen still has an official Warden of the Swans and an official clock winder.
And so it was against this musty background that Meghan made the deliciously freewheeling choice to eschew a froufrou dress for her McQueen suit.
Short of getting a bullhorn and standing in front of Kensington Palace, the future royal could not have been making a more profound and loud statement about her intentions. With the $3,545 look, she was clearly signalling that she had no intention of demurely toeing the line or blindly acceding to the status quo.
Rather, this was Meghan boldly and confidently flagging her intention to do things her own way.
That approach went far, far beyond her choice of designer duds.
This year, in the wake of the Sussexes' dramatic decision to quit royal life, a spate of royal biographies about Harry and Meghan have hit the shelves and the picture they paint is of a woman wholly intent on forging her own professional path.
In Band of Brothers, esteemed royal biographer Robert Lacey's newly released addition to the list, he points to the day that, also in February 2018. Harry and Meghan joined William and Kate Duke and Duchess of Cambridge for the first (and sadly, only) Royal Foundation forum, a moment that led to Fleet Street breathlessly dubbing them the Fab Four.
In hindsight, on that day Meghan similarly was telegraphing her intention to maintain a steely, determined focus on gender equality, referencing the #MeToo and #TimesUP campaigns.
"Everybody nodded approvingly," Lacey writes. "Yet no one – neither on the stage, nor in the audience, nor even in the attentive and critical press pack – appeared to realise quite how revolutionary was this suggestion that the new recruit was making. Created in America only the previous month and linked to #MeToo, #TimesUp was a $13.8 million legal defence fund seeking legislation to discipline and punish companies that tolerated sexual harassment. Legislation meant politics – and in royal terms politics was simply taboo. It was a total no-no for the British royal family to endorse any cause, no matter how virtuous, that could be seen to take one political side against another."
The story that has emerged again and again is that Meghan was focused on not only pursuing the projects that mattered to her, no matter the establishment feathers that might ruffle, but pursuing them how she saw fit.
To wit, her decision to guest edit the September 2019 issue of British Vogue (end result: a worthy but kinda pretentious issue that flew off shelves); her choice to not appear on the cover because she thought it would be "boastful" and her idea to spontaneously write messages on bananas for sex workers.
In 2019 it was reported with a sort of prim horror that Meghan allegedly sent her staff emails at 5am, and was labelled "demanding" and "having high standards." (Oh, the temerity of all that ambition! Quick, send her to the Tower!)
Even in her non-working capacity, she defied Windsor custom with her A-list New York baby shower, controversial day out at Wimbledon, and giving an interview to Vanity Fair about her royal romance in 2017, a move hitherto considered a mortal sin in the eyes of The Firm. (Though it seems highly unlikely she would have done it had Harry not been wholly on board.)
All of this went down about as well as a committed vegan decked out in pleather rolling up for a grouse hunt on the Glorious 12th.
Given how much has happened this year alone, it seems nearly impossible that it is only a scant three years since a beaming Harry and Meghan fronted the press at Kensington Palace to announce their engagement in November 2017.
If there is a lesson here is to be a successful royal recruit, is to possess a certain blind fealty to tradition and a willingness to fall pliably in line.
While Meghan clearly wanted to make her new duchess career work, she also avowedly set own path, no matter that it might have put her on something of a fatal collision course with the royal machine. Rather than be subsumed by the morass, she retained a certain impressive intransigence to play by the long-established rules of the Windsor game.
And none – none – of this should have been a surprise because Meghan told us from the very beginning that she was going to be her own person, title or not. The Queen famously uses her signature Launer handbag to send signals to her courtiers and aides and on that February night, Meghan was doing exactly the same thing.
Alexander McQueen, the founder of the label, once reportedly said, "Give me time and I'll give you a revolution." He eerily could have been talking about Meghan's time as an HRH. All she needed was three years – and one McQueen suit – to spark a royal revolution.
• Daniela Elser is a royal expert and writer with more than 15 years experience working with a number of Australia's leading media titles.