Any society now engaged in transacting business in this state may exercise all of the rights conferred hereby and all of the rights, powers, and privileges now exercised or possessed by it under its charter or articles of incorporation not inconsistent with this chapter, if incorporated. Any such domestic society may, upon filing notice thereof with the commissioner of insurance, be deemed from and after the date of filing such notice to be fully organized under the provisions of this chapter or, if it be a voluntary association, it may incorporate hereunder. No society already organized shall be required to reincorporate hereunder, and any such society may amend its articles of incorporation from time to time in the manner provided therein or in its constitution and laws. All such amendments shall be filed with the commissioner of insurance and shall become operative upon such filing, unless a later time be provided in such amendments or in its articles of incorporation, constitution, or laws.