Those who have been ousted by the Sussexes include the couple's newly appointed private secretary, Fiona McIlwham and their hugely experienced communications chief Sara Latham, as well as their press officers, their social media expert and other members of their communications team.
The source insisted most accept their fate.
"The Duke and Duchess have a small team, less than 15 people. The team are very loyal to the Sussexes and understand and respect the decision they have taken," the source said.
"They are all close and supporting each other. The team are busy helping to set their Royal Highnesses up for the future and working on a series of final engagements."
The news comes after earlier reports in January that the couple had sacked a number of staff members from their Windsor residence, Frogmore Cottage.
"Outside of anything that is being decided between the private offices [the nerve centres of royal operations] and the British and Canadian governments this week, no-one here believes that the duchess will ever really return to the UK in a meaningful way," a source told Daily Mail.
According to the Daily Mail source, at least two permanent employees – a house manager and a cleaner – are being moved to other duties within the Queen’s household.
Other members of staff who are used on an ad hoc basis, such as chefs, maids and footmen, have been told their services are no longer required at the couple’s Windsor residence.
A source said: "The workers are already being offered other roles at Buckingham Palace.
"There is a skeleton staff there all the time, consisting of one cleaner and a house manager. Others work as and when needed.
"This has all come as a bit of shock. They took great pride in working for them and being at Frogmore."
While sources told the publication that no one is being made redundant because of the Duke and Duchess of Sussex's departure, there has been a knock-on effect on employees after their decision to relocate to North America for part of the year.
Harry and Meghan shocked the world on January 6 when they announced their decision to quit, and they left the royal family in a state of turmoil.
In a statement they said: "After many months of reflection and internal discussions, we have chosen to make a transition this year in starting to carve out a progressive new role within this institution."
They continued: "We intend to step back as 'senior' members of the Royal Family and work to become financially independent, while continuing to fully support Her Majesty The Queen. It is with your encouragement, particularly over the last few years, that we feel prepared to make this adjustment.
"We now plan to balance our time between the United Kingdom and North America, continuing to honour our duty to The Queen, the Commonwealth, and our patronages. This geographic balance will enable us to raise our son with an appreciation for the royal tradition into which he was born, while also providing our family with the space to focus on the next chapter, including the launch of our new charitable entity.
"We look forward to sharing the full details of this exciting next step in due course, as we continue to collaborate with Her Majesty The Queen, The Prince of Wales, The Duke of Cambridge and all relevant parties. Until then, please accept our deepest thanks for your continued support."
Queen Elizabeth was reportedly left "deeply upset" by the decision and began the task of fixing her family's future at a meeting at Sandringham on Monday, which involved Harry, Prince William and Prince Charles.
After the crisis talks, the Queen said she supported Prince Harry and Meghan's "desire to create a new life as a young family" in a statement.
“Today my family had very constructive discussions on the future of my grandson and his family,” the statement read.
“My family and I are entirely supportive of Harry and Meghan’s desire to create a new life as a young family.
“Although we would have preferred them to remain full-time working Members of the Royal Family, we respect and understand their wish to live a more independent life as a family while remaining a valued part of my family."