Below is a round-up of the birth announcements from British newspapers. Sources include a national paper (The Telegraph, The Times) and a broad range of local newspapers from across England, Wales, Scotland and Northern Ireland.
Sibling names are in brackets. No official surnames are included; any name ending in a surname is actually a middle name.
Boys:
Arthur William (Matilda Alice)
Bertie Bartholomew
Charles Ashton
Leo James Hugh
Finley John
Mars
Robert Oliver George (Frederick)
Rudy Arthur Odin (Digby & Barnaby)
Rupert Timothy Alan
William John
Zachary Robert (Summer)
Girls:
Audrey
Bunny Florence Francis
Claudia Alexandra (Phoebe)
Edie Willow
Isabela Anna
Leonie Cora
Serena Elena Rose (Flora Mary Isabella & Eliza Rachel)
Media Personality Birth Annoucements:
[g] Willa Grace (Kaleb Cooper)
I cross-reference older BAs to find the full names of the siblings, however often they are missing (especially the eldest siblings, or for half-siblings) which explains why you will sometimes see something like: George Henry (Lucy, Emma & Jack Arthur). "Lucy" and "Emma" may well have middle names as well; I simply cannot find them online.