(1) The Comptroller has the responsibility for carrying out the provisions of this Act.
(2) The Comptroller may, in relation to any matter or class of matter, delegate in writing to any tax officer or other person employed in carrying out the provisions of this Act any powers, functions or duties conferred or imposed on the Comptroller by this Act other than —
(a) the power of delegation conferred by this subsection; and
(b) the power to sanction prosecutions conferred by section 73.
(3) A delegation made under subsection (2) may be revoked at any time by the Comptroller and does not prevent the exercise of such powers, duties or functions by the Comptroller.
(4) Subject to subsections (5) and (6), a decision made and a notice or communication issued or signed by the Comptroller or the Comptroller's delegate may be withdrawn or amended at any time.
(5) Where the Comptroller, knowing all the material facts at the time, makes a decision that a person is required or not required to register, and the person accepts the Comptroller's decision, and subsequently the Comptroller withdraws the decision, the Comptroller's decision governs the liability or non-liability of such person for payment of tax on any transaction concluded or event which occurred before the withdrawal of the decision.
(6) Where the Comptroller, knowing all the material facts at the time, makes a decision as to the nature of a transaction concluded by a person, and the person accepts the Comptroller's decision, and the Comptroller subsequently withdraws the decision, the Comptroller's decision governs the liability or non-liability of that person for payment of tax on any transaction concluded before the withdrawal of the decision.