The large Union Flag seen briefly at the back of the RAF hangar is back to front. The diagonal leading white stripe should have the thicker part leading clockwise. The flag is only hung upside down with the larger white stripe trailing, as a sign of distress.
The registration of the vehicle in the opening scene does not match any format used in the United Kingdom.
The raid at the beginning of the episode is said to be near Hampstead Heath. The mansion has a W8 postcode, which actually covers parts of Kensington and Chelsea three miles away - Hampstead Heath comes under the NW3 postal area of London.