Assembly and Parade Act Article 22

As soon as the responsible person of an assembly or parade announces discontinuation or completion of the assembly or parade, the participants shall disband immediately.Any actions taken after the announcement of suspension or conclusion shall be the responsibility of the individuals involved. However, if the participants do not disperse, the person in charge should be responsible for advising and persuading them to leave.
中文原文 集會遊行法第22條
集會、遊行之負責人,宣布中止或結束集會、遊行時,參加人應即解散。
宣布中止或結束後之行為,應由行為人負責。
但參加人未解散者,負責人應負疏導勸離之責。

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