As an addendum to my previous post, a bit of internet-searching reveals 1959 saw a television opera of Miss Hargreaves, called ‘The Spur of the Moment’, and that Margaret Rutherford starred in a 1960 straight adaptation of the book, on television (I knew she’d done the play; didn’t know about the film.) Is there any way of tracking these things down?!
EDIT: the film was actually 1950, not 1960 – sorry