This episode takes place in August 1942 according to the opening subtitle. About 22 minutes in, Samantha Stuart asks Joe, her American serviceman boyfriend, to tell her about his home in California. She imagines "oranges and movie stars; everybody in huge cars." He replies, "Sure, even Lassie had his own limousine." Lassie was not a movie star in 1942 - the first Lassie movie,
Lassie Come Home (1943), was released in 1943.