Thank you everyone for your comments and research ! That is quite amazing chance that you (Chris) had a recent photo from plot 1B1930 with the Allen name. Also that my great grandmother Minnie, died on Feb 23rd, (1911) yesterday, the day we started discussing this. Kind of cool.
Many good family stories about this strong woman (Minnie Avis Kirkham). 6 children, the youngest, 1 yr when her husband (thomas) died at age 39. He was a Carman with the railway. She was allowed to place 3 of the younger boys in the Railway Servants Orphanage, until some were 14 years old, but they came home on holidays. She worked for the railway as a cleaner after her husbands death. (Both she and her husband died of TB. I have the bible given to one of her sons in 1902 when he left the orphanage at age 14.
Except for one of the children, all moved from Walthamstow by around 1930, arriving in Connecticut and Albany, NY area of USA.
Not sure I understand the rules for the 'reuse' of family graves and removal of headstones, but will be pleased to just visit Walthamstow and this cemetery, as well as St Mary's and other old landmarks.
I'm going to try to attach a headstone picture taken decades ago. It says "family" so I wonder if that has meaning.