Continuity mistake: Kirsten is referred to as a DC (Detective Constable) in the first half of the series and then as a DS (Detective Sergeant) in the second half. As these later episodes include flashbacks to before the previous episodes, she obviously hasn't suddenly been promoted.
Vigil (2021)
1 continuity mistake in show generally - chronological order
Starring: Rose Leslie, Suranne Jones, Adam James
Factual error: The insignia worn by the submarine crew is inaccurate, including the lack of a white patch behind the trade badges and a strange made-up version of the White Ensign. Also the Submarine service emblem of two heraldic dolphins has them facing the other way.
Trivia: Instead of the Royal Air Force, the series has a fictitious British Air Force with largely invented insignia. Ranks are taken from the RAF, but sometimes different rank insignia is worn (e.g. an air vice-marshal wearing air marshal's insignia and a flight lieutenant wearing flying officer's insignia, although another flight lieutenant wears correct insignia).