The date of commencing use (of a residential building/dwelling), however, no sooner than 21 days after the investor has notified the local building control authorities that such building has been completed (and if the authority has not filed any objections, in the form of a decision, within 21 days of receipt of such notification) or the date on which the aforementioned authority has issued a permit for use of the residential building/dwelling. The authority responsible for issuance of such a decision until 10 July 2003 was the architectural and building administrative unit of the local gmina or powiat office.