Circumstances suggest that it was a man so here are a list of all the male members of the Royal Family. Make of it what you will!
Direct Members of the Royal Family (all of whom have been ruled out according to BBC sources)
- HRH The Duke of Edinburgh
- HRH The Prince of Wales
- HRH Prince William of Wales
- HRH Prince Henry of Wales
- HRH The Duke of York
- HRH The Earl of Wessex
- HRH The Duke of Gloucester
- HRH The Duke of Kent
- HRH Prince Michael of Kent
Relations or spouses of members of the British Royal Family, some of whom barely consider themselves to be royal:
- Peter Phillips (The Princess Royal's son) (also ruled out in the BBC report)
- Vice-Admiral Timothy Laurence (The Princess Royal's 2nd husband)
- Viscount Linley (The Queen's nephew, son of the late Princess Margaret)
- Earl of Ulster (The Duke of Gloucester's son and daughter-in-law) and their son
- Mr Gary Lewis (The Duke of Gloucester's daughters husband)
- Earl of St Andrews (The Duke of Kent's son)
- The Lord Nicholas Windsor(The Duke of Kent's younger son)
- The Lord Frederick Windsor(Prince Michael of Kent's son)
- James Ogilvy (Princess Alexandra's son)
And now the really obscure royals known as "collaterals" mainly descendants of the younger children of Queen Victoria, King Edward VII, and King George V plus all their children and grandchildren if they happen to be female:
- The Earl of Harewood (grandson of King George V through his daughter Mary, Princess Royal), his second wife, and his children, and grandchildren, as well as the children and grandchildren of his now deceased brother, Gerald Lascelles.
- The Duke of Fife (female-line great-grandson of King Edward VII) and his children and grandchildren
- The Lady Saltoun (widow of Alexander Ramsay of Mar, a female-line grandson of Prince Arthur, Duke of Connaught and Strathearn, the third son of Queen Victoria), and her children and grandchildren
- The Marquess of Milford Haven (grandson of George Mountbatten, 2nd Marquess of Milford Haven, and great-grandson of H.G.D.H.
- The Countess Mountbatten of Burma (elder daughter of Louis Mountbatten, 1st Earl Mountbatten of Burma, youngest son of H.G.D.H. Princess Victoria of Hesse and by Rhine, and her family
Another interesting issue is that the person had crested stationery in a private residence in London which would rule out some of the above.