However, in the case of an operation to be performed at a place where such operations are frequently and regularly carried on or in the case of a transfer of oil for fire brigade purposes, the notice may, instead of being a notice given to the Port Manager within the time hereinbefore provided, be a general notice given to the Port Manager to the effect that such operations will during such period not exceeding 12 months from the date of notice, as may be specified therein, be carried on between sunset and sunrise. (Amended by Act 7 of 1972)