Classified National Security Information Protection Act Article 29

Classified information may be declassified by the official who authorized the original classification or his or her superior official based on the loss of the information's sensitivity even when the declassification event has not occurred or the duration of classification has not expired.
中文原文 國家機密保護法第29條
國家機密於保密期限屆滿前或解除機密之條件成就前,已無保密之必要者,原核定機關或其上級機關有核定權責人員應即為解除機密之核定。

English translation for reference only; the Chinese text prevails. Not legal advice.