The technology of the Fusée à chaine, the enamle dial ( Lange confirmed me that a perfect enamel dials requires a lot of time, and that there is a ratio of rejectino very high! ), and the fact that Lange produces only a few thousand watches per year may explain that!
Lange doesn't have the means to produce this piece in a non limited edition.
Well, that's what I think.
Best.
Nicolas