Enforcement Rules of the Income Basic Tax Act Article 20

The product(s) or service(s) proposed in an investment project that remain unchanged under Paragraphs 3 and 4, Article 16 of the Act shall include the product(s) or the service(s) proposed in an application for the alternation of an investment project which was approved before the promulgation of the Act by the central authority in charge of the relevant end-enterprise and for which no additional application for a change to the investment project as been submitted after the promulgation of the Act.The start-up of work as set forth in Paragraphs 3 and 4, Article 16 of the Act shall mean the work start-up date of a plant building construction project to be decided under applicable building construction laws and regulations; or the date of arrival of the first batch of production equipment at the business place or the production place, in the cases of a new investment project or a capital increase project.
中文原文 所得基本稅額條例施行細則第20條
本條例第十六條第三款及第四款所定未變更投資計畫之產品或服務項目,包括營利事業於本條例施行前已取得中央目的事業主管機關准予變更投資計畫產品或服務項目之核准函,且於本條例施行後未再申請變更者。
本條例第十六條第三款及第四款所定開工,屬新建廠房之案件,依建築法令之規定;其他新投資或增資案件,為首批設備運抵營業處所或生產場所。

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