IMO, the two white blocks at the front of the rest of the blocks, are superstructure modules. Whose superstructure? The LNG carrier being built next to the carrier. The boxes are left in a way that the cranes can lift and place them in that ship.
Before the LNG carrier to the right was laid there, that area had been storing superstructure modules for various commercial ships under construction. Now the area is filled up by a ship, the storage area has to move to somewhere convenient. As for the rest of the blocks, they are unpainted and in primer grey. IMO, they are building superstructures in that shed.