King Charles’s attempt to rebrand his disgraced brother, Andrew, might not be going exactly as planned. After the King stripped the former Duke of York of his titles and honors, the palace announced he would simply be known as Andrew Mountbatten Windsor, living a low-profile life on the Sandringham estate. But now, insiders say the late Queen Elizabeth’s 1960 Privy Council declaration is coming into play—and it could once again change how Andrew’s name is styled.

The former prince will soon move out of Royal Lodge and start his new life in Sandringham, but before that happens, the issue of his name change remains unresolved. When Queen Elizabeth originally created the family last name of Mountbatten-Windsor, it included a hyphen, combining Prince Philip‘s Mountbatten name with the Windsor dynasty. However, Buckingham Palace‘s announcement about Andrew’s new name included no such hyphen.

Just before Andrew was born in 1960, Queen Elizabeth signed a decree stating, “Now therefore I declare My Will and Pleasure that, while I and My children shall continue to be styled and known as the House and Family of Windsor, My descendants other than descendants enjoying the style, title or attribute of Royal Highness and the titular dignity of Prince or Princess and female descendants who marry and their descendants shall bear the name of Mountbatten-Windsor.”

According to the Times, Mountbatten Windsor (without a hyphen) was “the version Andrew preferred.” However, Buckingham Palace now “is considering introducing a hyphen in accordance with his late mother’s wishes.” Other royals using the hyphenated name include Prince Harry‘s son, Prince Archie, whose name on his birth certificate reads Archie Harrison Mountbatten-Windsor, and Princess Anne, whose name on her marriage certificate uses the hyphenated surname.

Royal historian Ian Lloyd told the outlet he “was quite surprised when the palace statement came out giving Andrew’s name without a hyphen, given the historic precedent for one.”

After reaching out to the palace for guidance, the Times reported, “It is understood that Buckingham Palace, which has now checked the privy council declaration made by the late Queen in 1960, may use a hyphen in future when referring to Andrew.”