Section 32-11-643 - Acceleration upon delinquency(1) Failure to pay any installment, whether principal or interest, when due shall ipso facto cause the whole amount of the unpaid principal to become due and payable immediately at the option of the urban district, security holder, or trustee therefor initiating foreclosure proceedings, the exercise of such option to be indicated by the commencement of foreclosure proceedings for not only each delinquent installment but also all other unpaid installments of any assessment.(2) At any time prior to the day of sale, the owner may pay the amount of delinquent installments, with accrued interest, all penalties, and cost of collection accrued, including but not necessarily limited to any attorneys' fees, and shall thereupon be restored to the right thereafter to pay in installments in the same manner as if default had not been made.L. 69: p. 801, § 156. C.R.S. 1963: § 89-21-156.