From Loong, S.K. (1952), St. John's Hall: History and Register, p. 50.
From 1950 onwards, St. Paul's had been occupying the West Wing (on the left of the photo) of St. John's. In 1955, St. John's moved to Pokfulam Road and St. Paul's took over the whole premises.
It's seems that there's a church on the upper right hand corner of the photo. But I'm not sure the name of it or whether it still exists!