In this section, “legal holiday” means: the day on which a legal holiday, as defined under § 1–111 of the General Provisions Article, is observed; or a federal legal holiday. Notwithstanding any other law, when the last day to pay a tax, file a tax return, or perform any other act that relates to taxes under this title falls on a Saturday, Sunday, or legal holiday, performance of the act is timely if the act is performed on the next succeeding day that is not a Saturday, Sunday, or legal holiday. The last day to perform an act described under subsection (b) of this section is the last day of any authorized extension of time.