No such preliminary certificate shall be valid after one year from its date, or after such further period, not exceeding one year, as may be authorized by the commissioner, upon cause shown, unless the 500 applicants hereinafter required have been secured and the organization has been completed as provided in this article. The articles of incorporation and all other proceedings thereunder shall become null and void in one year from the date of the preliminary certificate, or at the expiration of the extended period, unless the society shall have completed its organization and received a certificate of authority to do business as hereinafter provided.