Regulations Governing the Establishment and Management of Offshore Island Duty-Free Shops Article 23

If goods entered into storage in a self-provided bonded warehouse by offshore island duty-free shops under Paragraph 1 of Article 15 are returned, the return shall be handled in accordance with the Regulations Governing the Establishment and Management of Bonded Warehouses and relevant Customs provisions.Where a return involves goods purchased from a manufacturer inside taxed zones for processing and export under the preceding paragraph, the application for return shall be submitted within three months from the day following the storage date.If the manufacturer has already received a deemed export declaration duplicate, it shall be retrieved for cancellation or correction. Any duties or taxes previously offset shall be remitted, and the competent Tax Office shall be notified. Returns requested more than three months after storage shall be processed in accordance with the clearance procedures of general imported goods, duties and taxes shall be imposed based on the condition of the goods at the time of storage.
中文原文 離島免稅購物商店設置管理辦法第23條
離島免稅購物商店依第十五條第一項進儲自用保稅倉庫之貨物因故退貨,應依保稅倉庫設立及管理辦法及相關關務法規辦理。
依前項規定辦理自課稅區廠商購買加工外銷品之退貨,應於進儲之翌日起三個月內提出申請,原供廠商已領有視同出口報單副本者,應予收回註銷或更正;其已辦理沖退稅費者,應繳回已沖退稅費,並通知所屬稅捐稽徵機關。
進儲三個月後之退貨案件,其退貨手續按一般貨物進口通關程序辦理,並按該貨進儲時形態課稅。

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