Samsung just started rolling out the Android 6.0 Marshmallow update for US Cellular Galaxy S6 Edge Plus users. The 6.0 update comes with build no. G928R4TYU2BPB6, and is installable by you as you don’t need to wait for the 6.0 OTA with this.
The full filename of the update is G928R4TYU2BPB6_G928R4USC2BPB6_USC and it comes in zip format. To install the 6.0 update on your Galaxy S6 Edge+ at US Cellular, you have to extract the zip to get the .tar file, and install the latter using Odin PC software.
We have provided the full guide at the link below, where you could download the firmware too.
Samsung recently released the 6.0 update for Galaxy S6 and Galaxy S6 Edge, along with Galaxy Note 5. While those were official 6.0 updates, the user-made 6.0 update is available for Sprint Note 4, ported from official 6.0 update for another Samsung device. Great!