But worth pointing out that for the first Landrover, from decision to proceed with a design to delivery of the first production vehicle, was from September 4th 1947 to July 19th 1948. And that was done without the benefit of any computer aided design. Admittedly it was a far simpler vehicle, but the facilities were nothing like what is available today either. In addition, it was like nothing Rover had ever built before, and using a completely new engine (designed in house, but several years earlier) to boot, even if it did use existing diffs and gear boxes.
Manufacturers, especially car manufacturers, are today pulling all stops to try and reduce the lead time for designs, taking advantage of the ability today to do all the design on a computer, and even 3D print prototype parts, and with Landrover planning to make the Defender replacement a completely new design in a completely new factory, this may be something they could pull off. Certainly thye will have been thinking about the design, and even preparing 'prototypes', including the DC-100, but I would not be surprised if they had only recently started a new design (hence the receding timeline).
John

