The prosecutor might offer a deal, but if you have a solid London v. Young case I would decline it as you are in a position to win your case outright.
At court they will open the doors probably about 15 mins before they start hearing cases, the prosecutor handling your case may approach you just to make sure you are there. When the judge enters everyone will be asked to rise, once the judge has taken his/her seat the clerk will call the name of the person involved in the first case of the day. When your name is called you will be asked to approach the podium and state your name for the record, then you will be asked to make your case. Make sure when you address the judge that you always refer to him/her as your honour as that is their proper title. At this point what will happen depends on the judge you've got. At my trial I lucked out and got a very experienced judge who was familiar with London v. Young. All he did was flip through my paperwork and ask a couple of questions of me and the prosecutor before quashing my ticket. The prosecutor in my case didn't put up a real fight, I think she realized that there really wasn't anything she could do. However don't assume it will be that easy, come prepared to educate the judge on the London v. Young case (and any other case law you want to use) and be prepared to make arguments supporting your position in case the prosecutor puts up a fight. Bring three copies of all the case law you are going to use, one for the judge, one for the prosecutor and one for you, you will be expected to have those ready to hand out if you are going to quote from them. I would go though the case law and on your copy put sticky notes next to any paragraphs you might want to quote directly from, that will make them easier to find when you are up there. I would also have good notes outlining the key arguments you want to make. I don't know if you have seen them already, but I've posted links to a couple of threads where other people outline their experiences in court, hopefully they are useful.
http://www.ontariohighwaytrafficact.com/topic2521.html
http://www.ontariohighwaytrafficact.com/topic1730.html