Wow, that service bulletin is pretty ridiculous. Over time this will corrode our headlights and wiring in the control modules of the LED board inside it. I noticed it happening on mine too. I have owned it for less than a month and it happened.
If you are reading GM Rep, PLEASE PUSH THIS UP AS THIS IS NOT SMART FOR THE ELECTRONICS OVER TIME, it could be a year, or probably after warranty. But this seems like a major problem with GM as all generations of GM trucks I see do not have the correct lights on more often than not, lights not working, high beams for low beams, wrong marker lights working for signals, cross wired low beams acting up with signals, etc as opposed to all the other manufacturers of cars and trucks with the proper lights mostly working no matter what year or model it is for what the light is intended for.