Sherry gives a danm fine answer, to which I would only add that the probation violation for not obeying all laws could result in the imposition of up to the maximum sentence on the 09 felony minus any time you already served in custody in that case.
Assuming you are on this site because you CAN'T hire an attorney, here is some practical advice.
You can clear the arrest warrant by placing yourself on Calendar and appearing before the judge who issued the warrant. Different Courthouses have different methods of doing this, but they all allow you to put youself of calendar one way or another. Call the Court and ask the Criminal Clerk what you need to do.
You should know that the judge may choose to punish you for failing to appear....
A person can withdraw their plea of guilty on no contest only in certain circumstances.
What it comes down to is needing to prove that you didn't know something then, that you do know now. This may be that new evidence has been found. It may be that you were misinformed about the law, or the amount of time you were facing by your lawyer, or it may be that you were misinformed about the strength or weakness of the governments case.
In any case, you will need to prove that the new...
There are lots of potential questions. Did they jump a fence? Pick a lock? How were they caught? What did they say? Was she given a ticket or was she charged with a crime (IE was she ordered to appear in court) or is thus a student punishment by a private club? Much more information (and a clear question) is needed before a lawyer can help you.
The facts you state are contradictory. You cannot be both on probation and diversion. If you were placed on differed entry of judgement (diversion) there is no conviction of a crime. If you were placed on probation there is a criminal conviction.
Technically you are in violation of the probation term that you obey all laws. You are Very unlikely to have your probation revoked over this, however, unless not drinking was a specific term. If you get a letter saying that a probation violation is bring filed, hire a lawyer who can collect all the relevant facts that I don't know. If not, I wouldn't worry about it.
Successful completion of probstion means that your probation was notvtetminayedcsnd a prison sentence imposed. You are OWED a reduction per the terms if your plea deal if you completed probation at all. If you are denied such a reduction you should have an attorney re-file the motion, and appeal if necessary. The differences between a felony and a misdemeanor conviction are important.