A pair of number 1s in the first photo, another in the second. Also had 1 GER just out of shot in the first photo!
Various others from yesterday: BNM 1 on a Range Rover, VZ 1 on a Zagato Aston, UKR 1 on a 730d, presumably the Ukranian Embassy and 1 CY on a BMW as well.
See it in Mayfair any time I pass through tbh. Used to be on a Bentley Turbo R. Always imagine an ex-RAF bloke with a big mustache and flying goggles driving it!