If you didn't enroll by the date the judge ordered, you are technically in violation of your probation, and the judge could impose sanctions up to the maximum term (which is six months in jail for a first offense DUI, minus any time already served). DMV will also withhold your license for failing to enroll in a court-ordered DUI program.
Since you are going back to court on your own, the judge will probably just re-refer you to the DUI program. It's the people who miss the deadline and don't take care of their obligations that make judges angry.
Please understand that this is a general discussion of legal principles by a California lawyer and does not create an attorney/client relationship. It's impossible to give detailed, accurate advice based on a few sentences on a website (and you shouldn't provide too much specific information about your legal matter on a public forum like Avvo, anyway). You should always seek advice from an attorney licensed in your jurisdiction who can give you an informed opinion after reviewing all of the relevant information.
Were you represented by an attorney when you were sentenced? If so, I would contact the attorney's office and see if they can assist you in having your case added to calendar. Different courts have different policies about re-referrals.
If you were not represented, I would consult with an attorney who regularly appears in the court you were sentenced in for advice. The best case scenario, is that you can easily take care of this your self. However, if this not the case, you should have assistance from an attorney who can help you maneuver in the system.
You are in violation of the court ordered probation that you agreed to at sentencing. The judge can sentence you to the maximum punishment possible. This doesn't mean, however, that that's going to happen. Hire an attorney who is familiar with the court you are in. What court are you out of? Often times an attorney can get you more time to enroll in LA county.
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