Nice finding
In one image the cuirass is a light armor, then a medium and then a heavy armor, having different AC, weight and price but the same description.
I'm going to go out on a limb here and suggest that the Cuirasses are placeholder armor sets. I would think they would distinguish between Leather, Studded Leather, Splint, Plate, etc as they start adding more detail to items and their descriptions. At least, that is my hope.
