What is the test for a defendant's concern that "he might unknowingly violate" the terms and conditions of his probation?

The People dismiss defendant's concern that "he might unknowingly violate" the condition. They believe his concern is "overstated" because the prosecution must prove that he willfully violated the condition. We agree that, as a general rule, "[a] court may not revoke probation unless the evidence supports 'a conclusion [that] the probationer's conduct constituted a willful violation of the terms and conditions of probation.' (People v. Galvan (2007) 155 Cal.App.4th 978, 982 . . . .)" (People v. Cervantes (2009) 175 Cal.App.4th 291, 295.)