EK schedule for winter did not show the 2 class on the evening run, however a corrective e-mail has now been sent, which adds up with what you can book...try booking 1st class after the 01/01/16 and you can only book the morning and lunch time flights.
Looking at configs I think that is roughly 700 extra seats p/w, while maintaining the 777 service for freight.
I was actually unaware of actually how bad the 380 is for cargo...1 single 777 can carry more than 3 x 380's combined !! No wonder EK want to keep with a triple as long as they can, but by adding the 2 class 380 they can have best of both worlds I suppose...increase capacity, keep growth going and keep the 777....for now !