Nozzers were new boys or new entries. The mess decks down Nozzers Lane were the New Entry Division prior to moving to the former Kite Balloon Station that became the New Entry Annexe in 1920. https://pbase.com/hms_ganges_museum/image/170732043
When the New Entry Division moved Instructors moved into 30, 31 and 32 messes. Prior to this they had been sleeping in the small room just inside the entrance to the Boys messes. This was until the CPO’s Mess was completed in 1928