Where the services referred to in paragraph 5(4) of Schedule 4 to the Act are supplied for any period, they shall be treated as being supplied on the last day of the supplier’s prescribed accounting period, or of each such accounting period, in which the goods are made available or used.

Where services specified in an order made by the Treasury under section 5(4) of the Act are supplied for any period, they shall be treated as being supplied on the last day of the supplier’s prescribed accounting period, or of each such accounting period, in which the services are performed.