When should the Union flag be flown at half mast?

Downing Street Union Jack at half-mast after death of Queen Elizabeth II | AFP

Union Jack 🇬🇧 half mast at Brompton-on- Swale church

Flags At Half Mast Over London (1941)

users have claimed that Union Flags are flying at half-mast outside

Why Do We Fly Flags Half Mast or at Half-Staff?

Union Jack Flags flying at Half Mast

Union flags fly at half mast in tribute to the late Duke of Edinburgh | SWNS

When to Fly the US Flag at Half Staff

Flag is flying at half-mast 21 December, 2022

The Union Jack flag at Whitehall is flown at half mast following the death of Queen Elizabeth II.

Half Staff Flags Explained | Flag Facts

Are Union Flags flying at half-mast across UK? As netizens worry for Kate and Charles

Union Flag at half-mast.

Union Jack at Buckingham Palace at half-mast after death of Queen Elizabeth II | AFP

Flying the Union Jack at half-mast

Union Jacks fly at half staff at the British Embassy in W...

Flags to fly at half mast until morning after Queen’s funeral

Peterborough Flying Flag Half-Mast After The Queen Dies

How to Fly the Union Jack the Right Way Up