The Act of the Establishment of Juvenile Reformatory Schools and Enforcement of Education Article 61

When a Reformatory School deems it necessary for a Student at any educational stages to extend his/her study duration, the Institution shall report to the competent authorities governing educational administration for approval. The extension of each grade shall not exceed two (2) years or his/her enforcement duration.
中文原文 少年矯正學校設置及教育實施通則第61條
矯正學校對於學生於各級教育階段之修業年限,認為有延長必要者,得報請主管教育行政機關核定之。
但每級之延長,不得超過二年或其執行期限。

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