and will our upload speeds go up after that.
Be careful what you wish for.
They could not possibly hande all the traffic on their current trunk cables. Haven't you noticed there already is a monthly limit for Internet. Most complaints are due to their habbit of signing up more customers than the system can handle.
I don't have Comcast Internet and have no limit, so I can watch all the streaming 4K I wish to watch. Also; there is one thing better than watching HDR / 4K. And that is to convert it into 3D for viewing. That is as good technology can get!