Pretty much what it sounds like, this was some early concept art on how the open jaw nose could be used on deWulf ships. Bottom left has the survey radar boom that initially inspired the idea (which may come back when capital survey sensors get rolled out).
Upper left was playing with the idea of having a rotating exposed radar array in the notch. This didn’t work out so much both from an in-universe perspective (since it’s incredibly vulnerable), but also because it looked to be terribly placed, as it offered only a tight band of sensor coverage. Upper middle has the now-standard collection of antennae and other misc sensors that are seen on most deWulf destroyers. This turned out to be the one that “looked best” for the smaller hulls. The final idea was using the jaw for launch bays for small craft. On larger (IE battleship) and larger hulls this is a viable idea, especially for the integral small craft bay and/or if the design only has one or two launch bays. But for smaller stuff, just for the small craft bay, the required proportions don’t work. One has to pry the gap open wider, and then it looks more like a gaping whale mouth than a jaw.