Although the Galaxy S7 handsets in the US started to receive Android 7.0 Nougat more than three months ago, US Cellular was not in a hurry. The new firmware it rolls out as we speak has about 1.5 GB in size and does not hold any surprises.
http://www.notebookcheck.net/US-Cellular-Samsung-Galaxy-S7-and-Galaxy-S7-Edge-get-Android-Nougat.213610.0.html