(1) The person or authority to whom any fees or charges are payable under regulations made under this Act may grant a rebate of such fees or charges to any person who is liable to pay them.
(2) Every rebate of fees or charges granted under subsection (1) shall—
(a) be based on the quantity of services used by the person liable to pay the fees or charges; and
(b) be offered on an equal percentage basis to any other person using a similar quantity of such services; and
(c) be granted in accordance with regulations made under this Act.