Goofs

In preparation for invasion during World War II, all navigational signposts and railway station signs were removed, to confuse potential enemy ground movements. In Episode #1.1 several scenes show signposts with names of villages and distances in miles.

Pervasive occurrence of the poor modern usage "you need to" and "I need you to" instead of the correct "you must". 1940s Brits never would have spoken like this.

One of the army lorries in the show, set in 1939 and before the war started, was a Bedford QL which didn't come into service until 1941.