Many thanks to all contributors to this post - what a fantastic response!
I had wondered about the Charlie Rowland link, and there is a Maude C Rowland as noted, who looks like she was quite a bit older than the rest of the family ("well on the way" as @avm228 notes). George C Rowland, if that was her father, seems to have had some interesting career changes after being a vocalist (working for the London Gazette, then latterly as a secretary to Richmond Hospital).
As to Cecilia (my grandmother) I have no absolute record of her middle name, just the initial on various censuses and work references. In the absence of a Rowland/White definitive marriage (possibly not in country), I might have to try looking for a link via James Charles (who was a talented musician, remembered by my mother as playing violin and the organ - also came out to Africa to visit his sister, but sadly took ill and died in Bulawayo).
I will look through the various suggestions and keep on plugging away. Thanks again.