(a) A grant in lieu of taxes, payable pursuant to § 12-18b, to a member municipality of The Metropolitan District that fails to pay an amount assessed by said district for sewer use shall be withheld, in whole or in part, as follows: If any amount assessed by said district to such municipality on or after January first of a calendar year and due on or before September first of such year remains unpaid on September first of such year, a withholding of such grant equal to the sum of such unpaid amount, plus the amount due in October of such year and a surcharge equal to five per cent of the sum of such amounts. If, on or by December first of such year, such municipality remits payment for such unpaid assessment amounts, any amount withheld from such grant payment pursuant to this subsection shall be paid to such municipality. If, on or by December first of such year, such municipality fails to remit payment for such unpaid assessment amounts, the Secretary of the Office of Policy and Management shall remit to said district, on behalf of such municipality, an amount equal to such unpaid assessment amounts, and to such municipality, by December thirty-first of such year, an amount equal to the amount withheld from such grant payment pursuant to this subsection. The secretary may retain an amount equal to the five per cent surcharge withheld pursuant to this subsection.

(b) Any member municipality of The Metropolitan District that fails to timely pay an amount assessed by said district for sewer use during the current or prior fiscal year shall be ineligible for early disbursement of any grant from the municipal revenue sharing account such municipality may be entitled to pursuant to § 4-66l.