(a) After the enactment of the zoning ordinance, the planning commission or the owners of fifty percent or more of the real property in the area to which the petition relates may petition to amend the zoning ordinance. The petition must be signed and be presented to the planning commission or the clerk of the governing body.

(b) Within sixty days after a petition to amend the zoning ordinance is received by the planning commission or the governing body, then the planning commission or the governing body must hold a public hearing after giving public notice. The public notice of the date, time and place of the public hearing must be published in a local newspaper of general circulation in the area affected by the proposed zoning ordinance, as a Class I legal advertisement, in accordance with the provisions of article three, chapter fifty-nine of this code, at least fifteen days prior to the public hearing.

(c) If the petition to amend the zoning ordinance is from the owners of fifty percent or more of the real property in the area, then before amending the zoning ordinance, the governing body with the advice of the planning commission, must find that the amendment is consistent with the adopted comprehensive plan. If the amendment is inconsistent, then the governing body with the advice of the planning commission, must find that there have been major changes of an economic, physical or social nature within the area involved which were not anticipated when the comprehensive plan was adopted and those changes have substantially altered the basic characteristics of the area.