If the taxpayer has paid as an installment of tax more than the amount determined to be the correct amount of such installment, the overpayment shall be credited against the unpaid installments, if any, and any excess shall be credited or refunded as provided in Part V of Chapter 18 of this Subtitle.  

Acts 1986, 1st Ex. Sess., No. 16, §1, eff. Dec. 24, 1986.