In what circumstances will a defendant change his sentence from a state hospital to a state prison?

In 1999, the parties negotiated a plea agreement and agreed defendant's prison sentence would run concurrent to his state hospital commitment. They agreed that, should defendant's sanity be restored, he would serve the remainder of his prison term in state prison. Thus, while the law may no longer authorize such a sentence, the parties are estopped from changing the sentence to which they already agreed. (Cf. People v. Hester (2000) 22 Cal.4th 290, 295 [defendants are estopped from complaining about sentences to which they agreed].)