Hi Pilot Frans,
Thanks for your response, both aspects seem to make good sense, especially when looking at photos of the starboard side where the conventional bridge does seem low in comparison to the deckhouse.

Hi John,

The additional bridge on portside can have to do with visablity forward. Perhaps not sufficant in certain ports/canals.
The box shape/tank shape thing on port aft is most possible the motorroom for the elevator. So Elevator can reach the (old) bridge level. By most ships the elevator stops one deck below the wheelhouse.

I have just noticed the extra structures above the bridge. There has always been a tank like structure on the port side above the bridge. But between 14 June 2012 and 6 Aug 2013 a second, bridge like structure has appeared on the starboard side above the conventional bridge. I have seen this type of thing on training ships in the past, but can anyone shed more light on these structures?