After the expiration of such thirty days from the filing of any such form, as provided in section 44-710, or at any time after having given written approval thereof, the director may, after a hearing of which at least ten days' written notice has been given to the insurer issuing such form, withdraw approval on any of the grounds stated in section 44-710. Such disapproval shall be effected by written order of the director which shall state the grounds for disapproval and the date, not less than thirty days after such hearing, when the withdrawal of approval shall become effective. An appeal from the decision of the Director of Insurance may be taken, and the appeal shall be in accordance with the Administrative Procedure Act.