The handy thing about being Queen, aside from having a day job that involves the occasional use of a sword (investitures you know), is that you can set your own schedule.
Aside from rolling up for the opening of parliament every so often, by and large it's up to one to decide when one wants to diligently leave the palace grounds to rub shoulders with the masses or give a speech to mollify the fractious, independence-minded Scots – and when one prefers to lie in bed with The Racing Post and an entire packet of Jaffa Cakes.
That freedom extends to holidays, with Her Majesty taking fairly clockwork breaks from the rigours of formally greeting nervous new ambassadors and occasionally opening a bridge.
In July, she heads north to Scotland where she stays until the beginning of October so she can enjoy fresh air, peace and battle the midges. Come Christmas, you will religiously find her at her Norfolk pile, Sandringham, where she stays from the end of December until February 7. Every. Damn. Year.
But this year, sticking to this set-in-stone timetable is shaping up to be problematic and for the first time, her clockwork breaks are looking more and more like a serious miscalculation.
To understand why, you have to go back to the end of her last getaway, when she returned to work in October. At the time, Buckingham Palace announced that she would be hitting the ground running – or at least moving at a surprisingly brisk pace – with the nonagenarian set for what was meant to be her busiest autumn in a decade.
The message was unequivocal – she might be fast approaching her centenary and preside over a family so troubled that Jerry Springer would demur from trying to help them sort out their dramas, but she was still wholly in charge.
That vim and vigour lasted just shy of three weeks, before this optimistic plan collided with the reality that the Queen is 95, and she experienced a still-mysterious health crisis in the second half of October.
First came the announcement that she was pulling out of a tour of Northern Ireland, then came the debacle of her being hospitalised overnight for the first time in eight years, a fact that the palace tried to hide in what resulted in an embarrassing farrago.
Over the course of the next couple of weeks, she also cancelled her attendance at the COP26 climate gabfest in Glasgow, failed to attend church which she usually does religiously (I couldn't help myself), ended up on doctor's orders to rest for the better part of a month and pulled out of the Remembrance Day ceremony at the Cenotaph at the eleventh hour because of a sprained back.
Whatever is ailing Her Majesty is clearly more serious than a scratchy throat or some achy joints.
As of the end of this week, it will be 52 days since she has appeared in public. She currently has no engagements on the publicly announced books between now and Christmas.
She has returned to work in some visible capacity, with Buckingham Palace releasing official shots of her meeting with dignitaries via video calls and holding an in-person meeting at Windsor Castle with the Governor of the Bank of England
But assuming she will stick to her normal timing, and won't return to any sort of public royal work until February 6 at the earliest, the anniversary of her father King George VI's death and her ascension to the throne, then that will mean she will have been out-for-the-count for 110 days.
And as Hamlet, a character who knew a thing or two about royal family ructions, said, therein lies the rub.
There might not have been a worse moment during her nearly 70-year reign for the Queen to disappear from public view for three months.
If ever there was a moment she was needed, as a figurehead, a unifying totem and a reminder of the dignity of royalty (well, the sometimes-dignity of royalty) then it is now.
For the House of Windsor, 2021 has seen the royals scrape their way through 12 months of publicity so bad, and plumbing such new depths of debasement, that Fergie's toe-sucking shenanigans now look positively humdrum.
The key actors to point the finger at for this dismal state of affairs are obviously Prince Andrew, and Harry and Meghan.
In August, Andrew became the first member of the royal family to be publicly accused of sexual assault, with Virginia Giuffre, a former sex trafficking victim of paedophile financier Jeffrey Epstein, claiming Her Majesty's son sexually abused her on three occasions. Andrew has strenuously and repeatedly denied her claims.
No matter if Andrew and his team of pitbull lawyers prevail in court. The stain of the friendship between Andrew and Epstein is a stain that will never come out for the royal family.
And then we get to Harry and Meghan and their self-assigned roles as palace agent provocateurs.
In early March when the sombre, wide-eyed duo sat across from Oprah Winfrey for two hours of angsty revelations, they unleashed the sort of barrage the palace has not faced since German bombers turned up in British airspace. The Sussexes' accusations of intentional racism, cruelty and a horrifying lack of compassion are ones that have indelibly marked the palace's image.
All of which is to say, there is a lot of repair work to be done to the monarchy – work that no one can more effectively and speedily achieve than a certain nonagenarian with a penchant for lime green.
And that obviously is why her extended break from public life is so problematic.
Rarely, if ever, has her unique rallying force been needed more in aid of the regal cause, and rarely has she ever spent so long, tucked away from view from everyone but her corgi pups.
As things currently stand, the next time we will most likely see Her Majesty will be on December 25 when she and her extended family attends St Mary Magdalene, the church on the grounds of Sandringham, and then later that day when her annual Christmas address is broadcast, an event that reliably triggers long and obsessive scrutiny of the array of family images behind her. (Moi? Guilty. As. Charged.)
That is an unpalatably long time in between regal boosters.
The Queen herself has famously quipped: "I have to be seen to be believed." Never has that been more true.
To be sovereign demands a degree of visibility that right now she is failing (for completely understandable reasons) to meet.
The coming year is going to be a huge one, both for the institution of the monarchy and the Windsors as a family.
On February 6, 2022, it will be 70 years since the then-Princess Elizabeth was given the devastating news of her father's sudden death, a tragedy which elevated her to the throne decades before she thought she would have to assume that searing responsibility.
For months, the monarchy has been gearing up for the Platinum Jubilee year, launching initiatives such as tree-planting initiative the Queen's Green Canopy, and with a four-day long weekend set down for the first week of June.
Already there are very ominous grey clouds on this horizon with Andrew's case hitting the New York legal system with gusto in May and June, and with Harry's memoir set to be released at some point, believed to be in the latter part of the year. Both of these seem very likely to present new and seismic threats to royal stability and will pummel the palace's image. Again.
Just how many blows can they absorb before permanent damage is done?
Unfortunately, after 70 years in the top job (Diana used to call her the "Top Lady") never has the institution the Queen swore to serve faced such a trial-by-family. Here's hoping she is busy recuperating from whatever her mystery health woes might have been and will enter 2022 fighting fit and ready for the PR battle of her reign. The Racing Post and the Jaffa Cakes will just have to wait.
• Daniela Elser is a royal expert and a writer with more than 15 years' experience working with a number of Australia's leading media titles.