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:
Adrian
Archie Percival Marsden
Aryan Evan
Freddie Julian Sowerby
Mason Michael
Oliver
Sebastian Edward
Stirling Oscar
Girls:
Cadi Elen
Grace Elizabeth
Isla Elizabeth
Isla Frances Anne (Henry & Grace)
Isobel Ruth (Emily Rose)
Madeleine Mae
Martha Elizabeth (Samuel "Sam" Piers)
Mimi Jean
Olivia Verity (Imogen Ruth & Charlotte Hannah)
Pandora Alexandra (Olive Sophia)
Persefonia Phyllis
Siena Saffron
Theodora Frances Rosebud
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.