California Code, Penal Code - PEN § 2963

(a) Upon a showing of good cause, the Board of Parole Hearings may order that a person remain in custody for no more than 45 days beyond the person's scheduled release date for full evaluation pursuant to paragraph (1) of subdivision (d) of Section 2962 and any additional evaluations pursuant to paragraph (2) of subdivision (d) of Section 2962.

(b) For purposes of this section, good cause means circumstances where there is a recalculation of credits or a restoration of denied or lost credits, a resentencing by a court, the receipt of the prisoner into custody, or equivalent exigent circumstances which result in there being less than 45 days prior to the person's scheduled release date for the evaluations described in subdivision (d) of Section 2962.