The airline has a significant backlog of 777s on order
DUB will deffinatly see the B77W before time.
I have a feeling the A343 is a stop gap between the A332 retirement a 3 class B77W being available, and also due the fact an increase of 60 daily seats is a minimal increase by EK standards.
As a rough guess Id expect daily B77W in mid 2013, possibly 2nd daily by the close of 2013.