This thing is definitely BOSS. Out of the 3 trims shown so far (WT, RST and Trail Boss) I definitely prefer the Trail Boss most. Unfortunately, it's probably not coming to market until late 2023 - 2024. Here's some design analysis and release schedule info I found:
The Silverado EV Trail Boss appears to have a matte black front fascia treatment similar to that of the Silverado EV WT, but with a design like that of the Silverado EV RST, including a gray lower bit for the bumper. We also spot a set of red tow hooks, as is tradition for the Trail Boss, plus a taller overall stance. The vehicle featured in the image also doesn’t have any Trail Boss badging, at least visible from this angle.
Under the matte-black fender liners, we see multi-spoke wheels with a black finish and wrapped in chunky off-roading tires. It’s also possible the 2024 Chevy Silverado EV Trail Boss may incorporate off-roading technology plucked from the GMC Hummer EV, such as CrabWalk mode.
General Motors has stated that it will launch the new 2024 Chevy Silverado EV Trail Boss following the launch of the Chevy Silverado EV RST First Edition and WT models. As such, it’s possible we’ll see the battery-driven Trail Boss around the fall of 2023.