When is the 2016 5 Series coming (F10 Refresh) in the U.S.

I am in the market for a new 550i. When is BMW bringing out the 2016 F10 version, i.e. when is the next facelift coming out, and what differences will it have over the current 2015 model.

Note: I am not inquiring about the next generation 5 series, just the next model refresh.

When is the 2016 5 Series coming (F10 Refresh) in the U.S.