There is a maintenance-specific forum
HERE.
BUT, I can tell you that each individual knife has it's own bevel from the factory. Becker isn't putting a laser on those bevels before it heads out, so your knife will differ from another guy's BK2. The key is to find the angle you want, and "reprofile" the edge to that angle, then maintain it yourself. Chances are, the factory bevel is way larger than 20º, and probably even larger than the 25º.
Take a sharpie and color your edge. Put your box on 20º and give it a pass or two. Check the edge to see if it is pulling sharpie off at the apex. If not, try the 25º, then check for missing marker. If neither touch the apex (the sharp part of the edge), you need to reprofile your knife.