Production Capacity is not unlimited, Mercedes Models that get good market acceptance are after 6-9Moths higher valued than what the Pre-Oder price was.
That happend to the last GLE in an extraordinary fashion. On top of that, at the German Dealerships called "Sternauto" you can oder your personal setup and engage into an agreement to let them have the car for the first six month. They will register on the Dealership for Testdrives and their Showroom and you get a massive discount. I did that twice with my last GLEs and sold them after another year still with substantial profit.