It was originally the old school then became the Seamanship School the later the Radar School, note the mortuary in the front of the picture plus to the right the rear of the messdecks (most likely 12 – 18 messes) down the long covered way backing on to Parsons Lane – see a later photo of the old school and note the bell tower up top is the same one. https://pbase.com/hms_ganges_museum/image/169361613