If the director notifies the insurer that the form is disapproved, it is unlawful thereafter for such insurer to issue or use such form. In such notice, the director shall specify the reason for his disapproval and state that a hearing will be granted within twenty days after request in writing by the insurer. No such policy, certificate of insurance, notice of proposed insurance, nor any application, endorsement, or rider, shall be issued or used until the expiration of thirty days after it has been so filed, unless the director shall give his prior written approval thereto.
SDCL 58-19-27