I think it'll most likely be the car they previewed a couple days ago, which also seems to be the lightly camouflaged 8 Series we've seen doing laps around an Italian track. That had a V8, and since it's M but not the M8, then maybe an M Performance car ? As far as being a "concept", it could be like the Concept M135i from 2012 (at Geneva too) that was just the M135i with some decals
