Acker Bilk, Chris Barber and Kenny Ball were also on the Jazz Boat, but they were not used in the film for contractual reasons.
The choreographer Lionel Blair (brother of lead actress Joyce Blair) is seen briefly in the dance scene on board the boat.
Filmed in 1959, and bearing a 1959 copyright statement during the opening credits, but released in 1960. A very visible wall calendar in one sequence reads September 1959.
The "Jazz Boat" used in the film was the MV Royal Sovereign. It was built in 1948 as a passenger excursion vessel for the General Steam Navigation Company (note the "G.S.N.C." on the gang's sweaters near the end of the film). In 1967 it was converted to an automobile and passenger ferry. In 1973 it moved to the Mediterranean and was renamed "Ischia" serving the Naples to Ischia Island route. It was sold for scrap in 2007.
The Chislehurst Caves in Kent were used for the club scenes at the beginning of the film. They are old chalk and flint mines dating back to at least the 9th century A.D. During WWII they were used as an air raid shelter for up to 15,000 people, and utilities and facilities were installed. In the 1950s it was turned into a tourist attraction and performance venue as seen in this picture.