Back in November Nikon filed patents for 24mm f/2.8 and f/3.5 full frame lenses. Few weeks ago, a new patent 201159288 was filed in Japan for a 24mm APS-C lens:
Two different versions of this lens were described in the patent – one with f/2.0:
and another one with f/2.8:
It seems also that Nikon is serious about adding a protective mount cover on their mirrorless camera. They filed another patent in Japan (201113399) for a mechanical mount cover that will prevent dust from getting inside the camera:
The mount cover is mechanical and it does not need battery in order to operate.