Just another update. I'm satisfied that the address I was trying to find became 3 Greenway Road. That is Blanche CLIFFORD'S address on the 1939 register and I was told it is now Leckwith Close. I used Google Maps to locate it and then the road it connects to, which is Sloper Road. Comparing that to the 1939 Register, the same road is shown on that. The houses on Leckwith Close still look like typical 1930s semi-detached of a type built far and wide. Many of them now have parking areas instead of front gardens. I grew up in a very similar one, in Portslade, Sussex.
The help I received on here, coupled with the group on FB, enabled me to be as certain as I can be that I found the address.
Many thanks for all the help and suggestions
Helen