Contact your PO immediately. Leave a message and get there first thing tomorrow. Make sure you are clean and sober. Yeah they can arrest you and violate you, but given your risk level and the fact that you call immeddiatly (Yes like tonight. Leave a message) and you are there first thing in the morning it is unlikely they will violate you if you pass the drug/alcohol test. Be sure to let your lawyer know what happened too and what you are doing (going there now...) so that if there is a problem he can be in court for you in the afternoon.
Next time look on line for one of those companies that will give you reminders of your next calendar appointments the day before the appointment.
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I agree with my collegue, who has covered all the advice points I would give a client here in NJ who had missed their probation appointment. Make sure you follow up as suggested and you have the best chance of not drawing a VOP. Good luck.
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