Hello and thank you for your question.
Many times when I was on the bench and there was a commercial driver, at the date of their trial, the officer and the defendant would go outside and usually come to some sort of disposition. The typical dispositions would include where the officer would drop the first count and add a second count that would be a non-moving municipal infraction, without a point. The second disposition, usually if you had an attorney present, would be to dismiss the matter all together in the interests of justice.
Thirdly, if you ask for a trial date, the officer may no show (and believe me that does still happen on many occassions) and the ticket is dismissed.
Another idea, would be to request for a trial by declaration. You have to pay the ticket bail amount up front, but you get a preview of what the police officer's testimony
will be. If you loose, you are still allowed to request for a trial de novo
) and then you can try the above options that I previously mentioned.
You need to go to the court and ask to do the trial by declaration since they already gave you an arraignment date, that is your first appearance where you go on the record and make a plea--guilty, not guilty, no contest (which is the same as a guilty plea basically).
If I were you, I would do the trial by declaration first. If that does not work out in your favor, then do the trial de novo. By the time the trial comes around, the officer may not be present or not have an independent recollection, and the Judge will dismiss your ticket in the interests of justice.
Best wishes--but don't give up--I have seen it both ways, on the bench and representing defendants with traffic tickets--and the longer you drag it out--usually the better for the defendant, especially one who has a commercial license.