Episode #1.2 - S1-E2
Factual error: The settlers prepare to burn Verity at the stake as a witch. Witches were never burned in England or her colonies; they were hanged.
Episode #1.3 - S1-E3
Factual error: Billy is called up into a specific unit of the Royal Artillery. This didn't happen. He would first have been sent to a Royal Artillery training depot and only after training would he have been assigned to a unit.
Factual error: Every Time the Shadow Raiders deploy to Somalia, they use a Blackhawk nicknamed "Adele" for their missions. I can understand the helos being transported via fixed-wing aircraft, but on their last mission they leave Georgia, and reach Somalia the same day, flying in the Blackhawks. It would take them some 15-20 hours not including fuel stops. Yet the mission is completed in the time it takes to find a bomb in downtown Atlanta.
Episode #1.3 - S1-E3
Audio problem: Elaine refers to someone's "ChatsApp" account, but her lip movements show she is actually saying "WhatsApp." (00:13:55)
Episode #4.9 - S4-E9
Factual error: Renate escapes from the prison in a Morris Ten Four, with the badge visible on the bonnet. However, this designation was not introduced until 1935 and the episode is set in 1931.
Other mistake: There is a countdown on the movie screen. It is then reflected in Dusty's glasses. But the numbers are not reversed in the glasses. (00:41:00)
Factual error: ACC Pat Gallan wears the ribbon of the Queen Elizabeth II Diamond Jubilee Medal. The medal was issued in 2012. Her medals would be correct for 2017 when the series was made, but not 2007 when it is set.
Visible crew/equipment: When Adrian is getting something from the snack machine, the cameraman can be seen in the snack machine's reflection. (00:26:30)
Boundaries - S4-E3
Continuity mistake: Alex and his mom are talking with Grandma about masturbation. Alex is in his school uniform shirt but for one shot he has a hoodie on, then in the next shot it's gone.
Factual error: In the last 2 episodes of series 2, when anyone uses a phone box it has the the BT Piper logo on the outside, which wasn't introduced until 1991 - six years after the series is set.