Section 14. (a) Appropriations for other than ordinary maintenance, unless otherwise specifically provided in the appropriation, shall be available for expenditure in the 2 fiscal years following June 30 of the calendar year in which the appropriation is made and any portion of such appropriation representing encumbrances outstanding on the records of the comptroller’s bureau at the close of such second fiscal year may be applied to the payment thereof any time thereafter. The unencumbered balance of such appropriation shall revert to the commonwealth at the close of such second, or other designated, fiscal year; provided, however, that appropriations for other than ordinary maintenance financed by the sale of bonds and notes, unless otherwise specifically provided therein, shall be available for expenditure in the 5 fiscal years following June 30 of the calendar year in which the appropriation is made and any portion of such appropriation representing encumbrances outstanding on the records of the comptroller’s bureau at the close of such fifth fiscal year may be applied to the payment thereof any time thereafter. The unencumbered balance shall revert to the commonwealth at the close of such fifth or other designated fiscal year.

(b) Notwithstanding paragraph (a), the comptroller may create restricted spending accounts for the management of encumbrances in expiring accounts funded by bonds and notes; may transfer encumbered funds from said expiring accounts into said restricted accounts; and may expend said funds following the receipt of duly authorized and properly completed payment vouchers; provided that nothing in this subsection shall authorize the encumbrance or expenditure of uncommitted funds in said expiring appropriations accounts.