Interesting few facts I learned today from reading ‘
And What Do You Do?’: you cannot sit in the presence of a Monarch or be above one (like a balcony). So on walkabouts or visits to community centres or schools, if you need to sit down, tough luck (protocol wise).
Also, when they wanted to change the surname Saxe-Coburg and Gotha due to anti German feeling Plantagenet was put forth as an idea by one Lord (however deemed too ‘theatrical’), Plantagenet-Tudor-Smith (Tudor was too closely linked to Henry and his wives and the Stuarts beheaded on of their own). Guelph was also suggested due to medieval links.
Due to the fact that the Queen inherited the throne and took on her husband’s surname of Mountbatten, Prince Charles and Princess Anne had the surname Mountbatten. However Churchill stopped the Queen trying to incorporate the Mountbatten name and had forced her into a declaration that the royals would be known only as the House and Family of Windsor. An amateur expert on the monarchy said that when her next child would be born, he/she would be a bastard as they had the mother’s surname (he felt very strongly about children being born with their mother’s maiden names). He wrote to the prime minister saying
“When the new baby is born, as matters now stand it will bear the Badge of Bastardy namely, its mother's maiden name”. Subsequently to stop any future children being labelled bastards, she made a new declaration saying that she had adopted Mountbatten-Windsor as the name for all her descendants who did not enjoy the title of His or Her Royal Highness 11 days before Andrew’s birth.
this article goes into more detail:
https://amp.theguardian.com/uk/1999/feb/18/monarchy