Arevalo

*824 This case arises out of a statutory anomaly that requires a trial court to use one formula to calculate presentence conduct credits when placing a defendant convicted of a violent felony on probation, but requires the court to use another formula to recalculate those credits if that person later violates probation and is sentenced to state prison. Defendant Rodrigo Arevalo was placed on probation after pleading no contest to a felony count of continuous sexual abuse of a child under 14 years old. Before being placed on probation, he waived some of the custody credits he had accrued while in jail in accordance with People v. Johnson (1978) 82 Cal.App.3d 183 , 147 Cal.Rptr. 55 ( Johnson ). This waiver left him with a total of 365 days of credits: 183 credits for time served (actual credits) and 182 credits for good *825 behavior (conduct credits) under Penal Code section 4019. 1 At the time of the waiver, the trial court mistakenly indicated that Arevalo would be entitled to the full 365 days of custody credits if he were eventually sentenced to prison.

The following year, Arevalo admitted to violating his probation, and the trial court sentenced him to six years in prison. In…