While the direct output from the pack may go to the flight deck first, there are no pressure bulkheads between the flight deck and the outflow valves. In fact, numerous blowout doors will open if there is any significant pressure differential between compartments. Once the outflow valves open and regulate the cabin pressure to 25000', that is the pressure altitude for the entire airplane. The only "comfort" part of it is that the temperature of the flight deck can be regulated directly, but the main deck will likely stabilize at a much lower temp.