I've looked at the electoral registers
I can see Frank Penny from the 1949 register at 25 Allfarthing Lane, there are 8 people listed at no. 25 and I suspect the building was perhaps split into flats/rooms.
Apart from a couple of changes the same 8 people including Frank were still listed at 25 Allfarthing Lane each year till the register that is in force from Feb 1959 to Feb 1960 which has no number 25 Allfarthing Lane in the register. It goes straight from 23 to 27.
BUT for that same year, there are 8 people listed at 2 Huguenot Place still in the Borough of Wandsworth and 6 of those 8 including Frank, are identifiable as being at 25 Allfarthing Lane in previous registers.
These 6 including Frank , are still listed at 2 Huguenot Place for the register in force Feb 1965 - Feb 1966
which is the last year I have access to.
Hopefully a death cert/burial record for Frank will confirm his address at the time he died as would a death cert/ burial record for his wife
Why the change of address for everyone in the property? I suppose its possible that maybe due to damage during the war, the building was declared unsafe and they'd finally got round to demolishing it?
You'd need someone more experienced than I with the London area to give an informed opinion on that.
Boo