3.70-3.82 GHz is to be cleared in the top 50 economic areas of the United States by December 5, 2021. Initially, the Atlanta, Baltimore-Washington, and Denver areas are excepted from this requirement due to the important teleports located in those markets. Also, Honolulu is excepted altogether since the C-band reallocation doesn't apply outside of the contiguous US.
3.7-4.0 GHz is to be cleared in the entire CONUS by December 5, 2023. At that point, no satellite signals targeting the CONUS will be able to use 3.7-4.0 GHz. Virtually all registered ground stations will have had new LNBs and filters installed that won't let them receive signals in that range anyway, plus many of the C-band satellites located over the CONUS are going to be replaced with new satellites that only work in the 4.0-4.2 GHz range.
Keep in mind, these aren't hard deadlines, but the satellite operators will face financial penalties if they aren't able to meet these dates.
