In what circumstances will the Court allow the prosecutor to amend the charge to include the intentional infliction of grievous bodily harm?

In People v. Hopkins, supra, 39 Cal.App.3d 107, 113 Cal.Rptr. 880, after the defendant waived jury trial the prosecutor amended the information to allege the intentional infliction of great bodily injury on the victim during commission of the offense. The newly added enhancement increased the possible minimum prison term on conviction from 5 years to 15 years. Finding that subjecting the defendant to trial without obtaining a new jury waiver was error, the appellate court reversed without any discussion of the reversible per se/harmless error question. (Id. at pp. 113-120, 113 Cal.Rptr. 880.) Because the error was clearly prejudicial under any standard, the decision does not necessarily support appellants' characterization of the case as falling in the reversible per se column.