A voter may return a vote–by–mail ballot to a local board: by mail; in person during regular office hours; through a ballot drop box; or through a duly authorized agent in accordance with subsection (b) of this section. A voter may designate a duly authorized agent in accordance with § 9–307 of this title to return a vote–by–mail ballot to a local board during regular office hours. Notwithstanding § 9–307(b)(4)(i) of this title, an agent is required only to: witness the voter mark the ballot and place it in an envelope; and return the ballot to a local board.