Time for performance of acts when last day falls on Saturday, Sunday, or legal holiday.

When the last day prescribed administered by the Office of Tax and Revenue for performing any act falls on Saturday, Sunday, or a legal holiday, the performance of the act shall be considered timely if it is performed on the next succeeding day which is not a Saturday, Sunday, or a legal holiday. For the purposes of this section:

(1) The last day for the performance of any act shall be determined by including any authorized extension of time.

(2) The term “legal holiday” means a legal holiday in the District of Columbia.