California Code, Government Code - GOV § 56705

(b)(1) Notwithstanding subdivision (a), in cities with a population of more than 100,000 residents that are located in a county with a population of over 4,000,000, no petition shall be accepted for filing unless the signatures thereon have been secured within 90 days of the publication of the notice required pursuant to Section 56760 and the petition is submitted to the executive officer for filing within 60 days after the last signature is affixed. If the elapsed time between the date on which the last signature is affixed and the date on which the petition is submitted for filing is more than 60 days, the executive officer shall file the petition in accordance with Section 56709.

(2) This subdivision shall not apply to a petition for a special reorganization, as defined in Section 56075.5. Subdivision (a) shall apply to a special reorganization, as defined in Section 56075.5, regardless of the number of residents in the city or county in which signatures have been secured on the petition. This paragraph is declaratory of existing law.