Margery or Marjorie?

The characters' names are a very important aspect of Jane Shaw's stories and were all given very careful consideration; so much so that she would write stories and leave spaces where the names should be, only filling them in later on after the characters had been well established and a suitable name could be given to them. Even before you meet them, the names Susan, Charlotte and Midge tell you a great deal about them. The same is doubly true for the Gascoignes. So it's a bit surprising that Midge's real name varies a little. In most of the books, when she gives her real name it is spelled Margery, but in Susan Rushes In and A Job for Susan the spelling is Marjorie. A bit unusual for an author who took such care over her characters' names.