Revocation of defendants Proposition 36 probation was premature because the prosecution had failed to make three separate formally noticed petitions before revoking his probation solely for drug-related reasons. The court here counted the number of violations admitted rather than the number of formal revocation proceedings. The People conceded on appeal that this was error, but argued that the court had also found defendant to be unamenable to treatment, and that furthermore, the procedural issue was waived by defendants failure to object. The Court of Appeal disagreed, noting that the court had failed to reach the amenability issue because it had already determined that the defendant had more than three violations of probation. The matter was remanded for a hearing on the issue of amenability to further treatment. The court found no waiver of the issue due to the fact that the trial court and all counsel clearly misunderstood the requirements of section 1210.1.