Corrected entry: In both scenes showing an oncoming steam train rounding a curve, the railway track has modern concrete sleepers rather than the wooden ones that were the only type used at the time. The scene at the railway station has the correct wooden sleepers.
Corrected entry: When the car chase starts, the black police car is a Wolseley. It crashes and is seen again as a Wolseley but when it arrives at the barn it is a Rover.
Corrected entry: The Morse code used in the movie is mostly numerical, even in places where it is supposed to be alphabetical according to the plot. When an interception operator gives Jericho her headset to listen to an ADU transmission similar to what he was looking for, it is all digits, not suitable for an Enigma machine. (01:03:10)