Royal Protection Officer Simon Morgan, 52, who served in the Queen’s security detail, confirmed that the process began shortly after Charles became monarch.
He said: “Even the king said in his acceptance that he will take this role for as long as life allows him to… it’s got to be in the back of your mind, and from the police, we’ve got to start planning again for the future.”
Sources within the royal household say while Charles continues to carry out official duties, officials from the Cabinet Office and Buckingham Palace have already begun practical walk-throughs of the Menai Bridge protocol.
A senior palace aide, who asked not to be named, said: “These are rehearsals no one wants to do, but everyone has to be ready. Every detail is planned – from who calls whom to how flags are lowered.”
The plan dictates the king’s private secretary will be the first to notify the British Prime Minister and the Privy Council Office of the death.
From there, a series of scripted calls – known as the “call cascade” – will inform cabinet secretaries, ministers, and senior civil servants.
Once the cascade is complete, flags across Whitehall will be lowered to half-mast and a statement will be issued by Buckingham Palace.
As with Queen Elizabeth‘s death, the day Charles dies will be referred to as D-Day, followed by D+1, D+2 and so on.
Prince William, 42, will immediately accede to the throne, while Catherine, Princess of Wales, 43, will likely be styled Queen.
