It varies from probation department to probation department, so theres no telling. If you have a P/O who will have your levels tested (which would require a GC/MS to give quantitative values - not exactly a low-cost endeavor), consider yourself fortunate. Some P/O's will opt for a cheapie assay screen only (which is a pass/fail endeavor and thus will not give a quantitative value) to keep costs down. So if you test positive on the assay, that can mean the revocation of your probation and jail time.