The main cast in the movie all chose their own surnames for their individual characters - each deciding on the surnames of their (Great) Grandparents who lived throughout WW2 - a homage suggested by Kerry Browne.
The 'dance sequence' was filmed in Stanley Halls, Croydon - an Edwardian building built in 1903 and in fact served throughout WW2; as during the war years, first aid courses are thought to have taken place at the Halls.
The movie's official song / theme, "Run Back To Me" performed by Elizabeth Chamberlain was specifically written for the film and refers to the relationship between the characters, Tommy & Elizabeth.
Apart from the Military Costumes & Props (which were supplied by Ronnie Papaleo & Colin Waterworth of Atonement (2007)), the dresses were designed and created by Award-Winning Costume Designer & Maker Ciéranne Kennedy Bell who has worked on many West End productions including Everybody's Talking About Jamie, Strictly Ballroom and the TV series, Black Mirror (2011).
In the dance sequence many of the extra's were dancing female to female; this was to symbolize the men who were absent and fighting during the war at the time.