The same thing happened with the Duchess of Cornwall for a considerable period after her marriage to the POW. I noticed that the pernicious and dreadful "Chattering Classes" Daily Mail was one of the worst culprits during the period 2005 to 2006 constantly referring to her as Camilla Parker Bowles for months after the honeymoon . Interestingly no English newspapers that I have seen, ever refer to the Duchess of Cornwall as Duchess Camilla. With regards to the Duchess of Cambridge being referred to by her maiden name even now, I too find this irritating. I used to feel the same about the 'Lady Di' sobriquet still being used, especially in the Foreign Press, to identify Diana, Princess of Wales throughout the eighties and all the way up till the time of her death! I found that really annoying! Even though she should never have been known as "Princess Diana" during her marriage, I still preferred it with teeth on edge, to 'Lady Di' which was inappropriate and declasse IMHO!