(2) With respect to an instrument payable at a definite time, the following rules apply:
- (a) If the principal is payable in installments and a due date has not been accelerated, the instrument becomes overdue upon default under the instrument for nonpayment of an installment, and the instrument remains overdue until the default is cured.
- (b) If the principal is not payable in installments and the due date has not been accelerated, the instrument becomes overdue on the day after the due date.
- (c) If a due date with respect to principal has been accelerated, the instrument becomes overdue on the day after the accelerated due date.