(1) A bill is dishonoured by non - payment:
(a) when it is duly presented for payment and payment is refused or cannot be obtained; or
(b) when presentment is excused and the bill is overdue and unpaid.
(2) Subject to the provisions of this Act, when a bill is dishonoured by non - payment, an immediate right of recourse against the drawer and indorsers accrues to the holder.