An amount required to be paid to TfNSW by a roads authority under this Division is payable--
(a) if the amount exceeds $2,000, by instalments of such amounts, payable over such period, as may be agreed on between TfNSW and the roads authority, or
(b) in any other case, within 90 days after demand by TfNSW or within such further time as TfNSW allows.