But I must disagree with your title for her. [PEDANT] As she is not the daughter of a Duke, Marquess or Earl, which would entitle her to the honorific "Lady" before her given name (cf Lady Di), she should correctly be referred to as "Fiona, Lady North". - Teeters
But I must gently disagree with you, without diminishing any appreciation of Air Marshal North's well-deserved advancement, since preceding the wife of a knight's title with her given name is surely normally only appropriate when there is more than one Lady X or, Heaven forfend, if Lady X is divorced and her former husband has remarried.
On a slight change of tack, interesting to note that the appointment of Second Sea Lord now ultimately merits the award of KBE rather than KCB.
Jack