modified
Unpaid
payable, owed, owing, outstanding, overdue, collectable, unsatisfied, unsettled, not met, matured, receivable, to be paid, chargeable, in arrears; see also unpaid 1, 2.
Suitable
fitting, proper, rightful, adequate; see deserved, enough 1, fit 1.
Expected
scheduled, anticipated, slated, promised; see expected 2, planned.
become (<strong><em>or</em> </strong>fall) due