Can an error in section 654 of the Criminal Code be assigned as an error on appeal?

" 'Errors in the applicability of section 654 are corrected on appeal regardless of whether the point was raised by objection in the trial court or assigned as error on appeal.' [Citation.] This is an exception to the general rule that only those claims properly raised and preserved by the parties are reviewable on appeal. This exception is not required by the language of section 654, but rather by case law holding that a court acts in excess of its jurisdiction and imposes an unauthorized sentence when it fails to stay execution of a sentence under section 654." (People v. Hester (2000) 22 Cal.4th 290, 295.)