I don't practice in WI but to give you some idea, in NV, when Parole and Probation arrests someone on an alleged probation violation, its an automatic 45 day hold. The PO can release the hold at any time, and realistically, cases headed to revocation hearings get there well before 45 days. But it is normal for a defendant to wait 2 or 3 weeks before a hearing. Get an attorney as soon as possible for the best chance at reinstatement. Good luck.
I hope what I've written here helps you, but remember, this answer isn't legal advice and doesn't establish an attorney/client relationship between us. To get actual legal advice, you need to speak to a criminal defense attorney.
If this person who is on a probation hold is still in custody, he should call the State Public Defender's Office. The jail usually has a phone that can be used for this purpose. If he has been taken into custody on a hold, the agent has 50 days in which to have a final revocation hearing unless good cause is shown for any delay. Be aware, he is out on supervision with a PO as an alternative to being behind bars. If his PO has reason to believe that he is violating any of his rules of supervision, the PO can order him held in custody while the PO investigates the allegations. This is just one reason why being on probation isn't always the best alternative to incarceration.
This communication is for the purposes of general advice only. This communication does not form any contractual obligation on behalf of the Attorney Stephen W. Sawyer or the Law Offices of Stephen W. Sawyer.
Sometimes no charges are filed as it was a rule violation, not criminal. Holds used to be 5 days and reissued twice before revocation is figured out yes or no. He can see an attorney right away. Call the PDs office.