did you finish your community service - just not in time? If not, get it done! They can revoke your probation for not doing it timely but if you have done everything else, and you have now completed the community service, it is not likely that they would revoke you. Follow the rest of the terms of your probation to the term.
You only get arrested if you don't go to court and the judge orders a bench warrant. If you make a good faith effort to do your community service and go back to court, most judges will give you more time. If you blow it off and don't go back to court, the judge will issue a warrant. As for the order, don't put faith in the police going after violation warrants first. Every day I see the warrant squad bring people in who have not completed community service or paid a fine. These are low risk warrants for the police but executing them lets them pad their statistics so you should do your community service and go to court.