I am surprised your case has been listed for a Case Management hearing (CMH).
When you responded to the SJPN did you simply plead Not Guilty to both charges or did you mention anywhere that you would be prepared to plead guilty to speeding if the FtP charge was dropped?
The CMH is to prepare the case for a trial. It identifies the issues in dispute, agrees what witnesses should attend, that sort of thing. Your case should need none of that, When you attend court arrive a bit early and ask to see the prosecutor for your case. Make your offer and hopefully that will cut matters short.
In the unlikely event that your offer is declined you will have to decide whether to defend the FtP charge or not.