PMDG wants this to be as close to real as possible. So they're simulating Boeing's delays as well.
Now if only Boeing would care as much about what they build and put real people in as the company that builds the plane for a simulator.
Rather impressive and sad at the same time that PMDG cares more about it's products and won't just throw something out there, while Boeing is flying real people around the world and has lost there standards, throwing anything out there.