When probation is revoked, the door to early release closes in a way that most people do not anticipate going in.
Here is why. Probation itself was the early release. When a judge sentences someone and then suspends that sentence in favor of probation, they are already granting the most significant form of leniency available, which is keeping the person out of custody entirely while the sentence runs. The probation was the deal.
When that deal gets broken through a violation, the judge revokes probation and orders the original sentence to be served. At that point the calculation changes fundamentally. The inmate is no longer serving a probation sentence with parole as a potential pathway. They are serving the original revoked sentence, and in most jurisdictions a revocation sentence is served without the early release mechanisms that apply to a standard sentence.
What that means practically is that on a 3 year original sentence with probation revoked, the expectation in most states is that the full remaining balance of that sentence gets served. The exact calculation depends on how much time was already served before probation was granted, what good time credits if any apply under the state's rules for revocation sentences, and what the specific language in the original judgment and commitment order says about revocation terms.
The shortest path to a clear answer is for his attorney to review the original sentencing order and the revocation order together and calculate what the actual remaining time looks like under the applicable state law. That is the document-based answer, and it is more reliable than any general estimate.