Amendments to this charter may be adopted by any of the following methods:
1. By local law adopted in accordance with the provisions of this charter.
2. By vote of the electors of the city upon the petition of electors of the city, an amendment may be adopted.
(a) in relation to the manner of voting for the elective officers of the city or any of them, or
(b) abolishing any elective office or offices or creating a new office or offices, including if so provided a transfer of powers to the newly created office or offices or a disposition of the powers of any office abolished, but no such amendment shall repeal or change any limitations contained in this charter on any power.
(c) such amendment may be adopted in the manner following:
(1) Not less than fifty thousand qualified electors of the city may file in the office of the city clerk a petition for the submission to the electors of the city at the next general election therein held not less than sixty days after filing of such petition of such a proposed amendment or amendments to the charter to be set forth in full in the petition. The petition may be made upon separate sheets and the signatures of each shall be authenticated in the manner provided by the Election Law for the authentication of designating petitions. The several sheets so signed and authenticated when fastened together and offered for filing shall be deemed to constitute one petition. A signature made earlier than one hundred twenty days before the filing of the petition shall not be counted. If within ten days after the filing of such petition a written objection thereto be filed with the office of the city clerk, the Supreme Court or any justice thereof of the first, second or eleventh judicial district shall determine any question arising thereunder and make such order as justice may require. Such proceedings shall be heard and determined in the manner prescribed by the election law in relation to judicial proceedings thereunder.
(2) If such proposed amendment or amendments receive the affirmative vote of the majority of the qualified electors of the city voting thereon, it or they shall take effect as prescribed therein.
3. In such other manner as may be provided by law.