Any regulations or provisions of these subdivision regulations may be changed and amended from time to time by the Council with such amendment being initiated by the Council, by a motion of the Commission or by a petition by any person; provided, such changes or amendments shall not become effective until they have first been reviewed and a recommendation has been made thereon by the Commission, or until 45 days after submission to the Commission if the Commission makes no recommendation within that time; and further provided, a public hearing shall be held by the Council, public notice of which shall be given in a newspaper of general circulation within the City, or by posting in three public places within the City not less than 10 or more than 20 days before the date of hearing.