The Duke and Duchess of Sussex were previously placed halfway down the page – below senior royals but above minor members of the family.
But after Queen Elizabeth II's death, the webpage has been updated.
Meghan and Harry have now been moved below the likes of the Duke and Duchess of Gloucester – and alongside Prince Andrew.
Prince and Princess Michael of Kent, who are not working royals, have been removed from the page completely.
The move appears to be consistent with King Charles' reported plan to "slim down" the monarchy during his reign.
Prior to their breakaway from the Royal Family, the Sussexes sat below Prince William and Kate, Princess of Wales on the page.
But around 15 months ago, they were moved to a spot below Princess Anne, Prince Edward and Sophie, Countess of Wessex.
This was interpreted as a move to reflect their status as non-working royals.
They now appear to have been "demoted" once again.
It comes as extracts are released of Valentine Low's book, due for publication in October.
Writing in 'Courtiers: The Hidden Power Behind the Crown', he claims that, during the initial deliberations on January 8, 2020, Queen Elizabeth II wanted all four royal households to work together on a Megxit solution.
Meetings were held at Clarence House before they were moved to Buckingham Palace while Prince William's private secretary, Simon Case, was also involved.
Five options were allegedly discussed, including giving the Sussexes a month off each year for their own activities.
An alternative was the idea that they could take on fewer engagements and spend most of their time doing other things.
It was taken as a given that blanket rules on not making decisions for financial or material gain would apply.
Mr Low quotes a palace insider as saying: "I think Meghan thought she was going to be the Beyonce of the UK.
"Being part of the Royal Family would give her that kudos. Whereas what she discovered was that there were so many rules that were so ridiculous that she couldn't even do the things that she could do as a private individual, which is tough."
Another said the Duchess would be unable to fit the model of a working royal, with the palace unable to accept "who she wanted to be".
Mr Low writes that it was Queen Elizabeth II who had the "very clear view: you can't be in and out".
He adds that any chance of "compromise" was taken off the table by the late monarch.
Meghan Markle and Prince Harry
TOBY MELVILLE
The Duke and Duchess of Sussex with the Prince and Princess of Wales
PETER NICHOLLS