The story takes place in 1955. The Austrian delegate, who also appears in flashbacks from 1932, is called count. Since the revolution of 1918, Austrians are not allowed to use nobility titles.
While Miss Marple and the inspector are reviewing Anthony Cade's account of his actions up until he found the body, Marple refers to the murder weapon as a revolver. However, when they discovered the body, the weapon they found was actually a semiautomatic pistol. Given her experience and precise mind, she would not make such an error.