Yes, but you will have to take two buses. The bus from the arriving EK flight will take everyone to the arrival terminal by default. When you get there, tell the agent standing outside or just inside the door that you need to be transported to the premium terminal (or main departure terminal, as the case may be), and you will catch another bus from there. (It would be wise to bring your boarding pass, if you printed it on-line, or your itinerary to show to the agents when you get off the bus at the arrival terminal.)