Here are my proposals for your consideration (#19, #20, #21 & #22).
The symbol is a letter 'b' which is cutted to represents letter 'b' and 'c' that stands for biss-code. As you can see, the first cut on the left side is a form of a Bite Fork Stabilizer. And on the right side, is a representation of codes on the right side is a section in the form of the letter 'c' is reversed horizontally which is divided into sections and colors. These are representation of the code which in this case is represented by the colors that became a symbol of the case levels and and the stages of solution.
I hope this short explanation of the story behind the symbol would helps. And please don't be hesitate to let me know if you have any revision request needed.