Cal. PEN § 11177.1

(a) Before a probationer or parolee may be returned to the sending state under this compact, he shall have a right to counsel and to a hearing before a magistrate to determine whether he is in fact a probationer or parolee who was allowed to reside in this or any other state pursuant to this compact, whether his return to the sending state has been ordered, and whether there is probable cause to believe he is the same person whose return is sought. At the hearing, the magistrate shall accept certified copies of probation or parole documents showing that this compact has been invoked and that the probationer or parolee has been ordered returned to the sending state, and these documents shall constitute conclusive proof of their contents. If the magistrate concludes that the probationer or parolee is subject to the terms of this compact, an order shall be issued forthwith directing the delivery to the sending state of the probationer or parolee.

(b) If the probationer or parolee or his counsel desires to test the legality of the order issued under subdivision (a), the magistrate shall fix a reasonable time to be allowed him within which to apply for a writ of habeas corpus. If the writ is denied and probable cause appears for an application for a writ of habeas corpus to another court, or justice or judge thereof, the order denying the writ shall fix a reasonable time within which the accused may again apply for a writ of habeas corpus.