[§271-26.5]  Change of address; responsibility; service of orders.  A motor carrier shall have, maintain and operate from a definite place of business in the State and shall display therein the certificate or permit issued by the public utilities commission.  The certificate or permit holder shall report any change of address or telephone number to the commission within five business days from such change.  Communications, correspondence and service of orders and other official documents shall be made upon the certificate or permit holder at the last recorded address on file with the commission.  Proof of service by certified or registered mail to the last known address shall constitute a valid service of any commission's order. [L 1978, c 66, §5]