The title of the film is nothing to do with the Doomsday Clock, which was not introduced until eight years after the events of the film, and is nothing to do with British Intelligence. As the character of Captain Drey explains in the film itself, it refers to Miller's Intelligence phone contact number which is Whitehall 1154.
Snapshots of the actual school, classrooms, and schoolgirls were shown before the end credits.
Epilogue: "The Augusta-Victoria college for girls, Bexhill-on-Sea, was the first and last school of its kind in Britain. It opened in 1932 and was closed in the summer of 1939."
The names on the Anglo-German Fellowship document are as follows: Eckhard Schafer, Jurgen Fischer, Kurt Weber, Heinrich Krause, Hans Fuchs, Werner Schmidt, Helmut Baumann, Frau Sofia Mayer, George Johnson, Lady Gillian Syth, Edward Chapman, Harold Cole, Mrs. Norah Briscoe, Raymond Davis Hughes, Dr. Arthur Owens, and Duncan Scot* (*The final letter(s) of Duncan's name were cut off in frame).