10For the purposes of this Schedule, and of section 7 of the [1978 c. 30.] Interpretation Act 1978 in its application to this Schedule, the proper address of a person, in the case of secretary or clerk or other similar officer of a body corporate, shall be that of the registered or principal office of that body, in the case of a partner of a firm shall be that of the principal office of the firm, and in any other case shall be the last known address of the person to be served.