Enforcement Rules of the Customs Act Article 2

Upon amendment of the Act or the Customs Import Tariff, the application of the provisions of the Act or the tariffs shall be governed by the following:1. For imported goods, the amendment thereto shall apply from the arrival date of the means of transportation. However, the provisions of the Act or the Customs Import Tariff shall apply from the date of application for release of such goods from a bonded warehouse for import, provided that the goods were originally stored in the bonded warehouse under Article 58 of the Act; or from the date of declaration for import thereof if the goods are approved for release from a bounded factory in accordance with Article 59, Paragraph 2, of the Act; or from the date of application for release of such goods from a logistics center for import if the goods were stored in the logistics center under Article 60 of the Act .2. For exported goods, the amendment thereto shall apply from the date of their release from Customs.
中文原文 關稅法施行細則第2條
本法或海關進口稅則遇有修正時,其條文或稅率之適用,依下列規定:
一、進口貨物,以其運輸工具進口日為準。
但依本法第五十八條規定存儲保稅倉庫之貨物,以其申請出倉進口日為準;依本法第五十九條第二項規定核准出廠之保稅工廠貨物,以其報關日為準;依本法第六十條規定進儲物流中心之貨物,以其申請出物流中心進口日為準。
二、出口貨物,以海關放行日為準。

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