Cargo waiting to load for next trip sent to 104, and unloaded goods from last trip initially held in 102. Better not to mix the two I guess. Our ships took a big load of cargo and mail in their seven holds.
Arrival hall needed for passengers to meet customs etc., whereas departing passengers went straight from the Boat Train etc., direct on board.
Apart from weekends there was always two mailships in Southampton.
Inbound arrived Monday morning at 0600 and the outbound ship left on Friday at 1300.
The move from inbound to outbound berth took place at the weekend.
It was done by the shore staff without engines, as you can see two black balls are hoisted on the signal mast.