Versions of s. 21.15(2)(b)(ii)

where the aggregate of the amounts charged for that taxable service by the person from whom the small undertaking acquired the service cannot be determined prior to the commencement of the service by the small undertaking, the aggregate of the amounts that, in accordance with the agreement between the small undertaking and that other person, are paid or payable by the small undertaking for the service, computed as of seven days prior to the commencement of the service or such later day as may be fixed by the Minister; and