Just FYI...Netflix, although it says "4K" is not really "4K".
The only way to truly get it in "4K" is to run it through the Netflix app on your TV and skip the Comcast box.
I've had my 4K box for about 4 months and apart from delayed Olympic events...you get nothing. I was hoping for World Cup in 4K...but
Heck even Direct TV and The Dish have dedicated 4K channels...they showed some of The Masters in 4K