I tried it set both to “t” depth, and the exact depth of the material, but both times the simulation does the same thing. I’m on build 855, on a Mac.
I simulated it with setting DOC to the thickness of your material and it simulated correctly. I am not sure why “t” is cutting deeper than the depth of your material.
I can’t open your file right now, but if you enter T for the breakthrough, it’s going to get through the material by a lot. If you want to end the cut at the bottom of the material, the breakthrough should be 0.