Gloucester City did lose 4-0 to Bristol in the FA Cup, but it was 1950, not 1939.
Chief Inspector Sullivan's cap has the Silito tartan the black and white chequered band. This was born by Scottish officers from 1932. They did not adopt this until 1972 in England and Wales.
Chief Inspector Sullivan salutes while not wearing headdress. The UK police like the armed forces do not salute without headdress.
Chief inspector Sullivan wears white gloves while in uniform an officer of his rank would wear brown gloves.