Regulations Governing the Management of Import/Export Clearance for Transportation means Article 46

Export cargos, transshipment cargos, import cargoes which are loaded by mistake, over discharged or untaxed due to transshipment, or ship’s stores, shall be declared to the Customs through Customs-stamped released shipping order/booking note, computer release notice or permit before loading and shipping. However, declared and released export cargoes shall not be loaded after 30 days following the date of release.
中文原文 運輸工具進出口通關管理辦法第46條
出口、轉口貨物、誤裝、溢卸、轉運未稅之進口貨物或船用品,應憑海關蓋印放行之裝貨單或託運單或電腦放行通知或准單辦理裝運。
但已報關放行之出口貨物,未於放行之翌日起三十日內裝船出口者,不得辦理裝運。

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