In San Francisco the DA's office will usually object to early termination of probation. If you have a good reason for early termination, and yours sounds like a good reason, then you should give it a try and have an attorney argue the motion for you.
These motions are heard in Department 18. They require 15 days notice and they hear them on Wednesday mornings. Since it's early termination you request, I would recommend doing a formal motion with declaration, instead of just filling out the judicial counsel two page form. The motion should request early termination and expungement, and can be done as one motion.
Aaron Bortel, Esq.
650 5th Street, Suite 508
San Francisco, CA 94107
You are going to need to file a motion for early termination of probation, then if granted, file a motion to dismiss the charge.
Judges usually grant these if you can prove some kind of hardship.
If you have anymore questions, please feel free to contact me.
If you were put on 5 years probation the ideal time to seek a modification is 2 and 1/2 years. You will not get an early termination unless you have completed all obligations under the terms of your probation. No unfinished classes, no unpaid fines. Even if you have done all that a judge may be disinclined to terminate someone early who blew a .17. No harm in asking though. I practice in SF.