DPReview has posted information from a recent Nikon interview. They have confirmed the corporation is working on a new mirrorless system and even hinted it is geared toward the high end. The latter thoughts come from a previous interview where they said they are focusing on the mid and high-end cameras. Could it be Nikon is working on a professional quality mirrorless system? Perhaps one which takes existing F Mount lenses. Could it be?
You can see the Nikon Rumor's Post here: https://www.dpreview.com/news/9148147105/official-statement-nikon-currently-developing-new-mirrorless-cameras