The expiration date of your visa is the last day you may use the visa to enter the United States. It does not indicate how long you may stay in the United States. Your stay is determined by the Department of Homeland Security at your port of entry.
In some circumstances, a person may be released from custody without bail and be given an order to appear, with certain conditions as governed and directed by a court-affiliated agency. Project Remand ('PR'), a Ramsey County pre-trial court service program, is one example of such an agency.
Probation is a county function in New York State, although in New York City, the probation department is run by the City government. The Division of Probation and Correctional Alternatives (OPCA) provides regulatory oversight and funding to local probation departments.