The Regulations Governing the Claiming of VAT Refunds for Goods and Services Eligible for VAT Purchased by Foreign Enterprises, Institutions, Organizations, or Associations Engaging in Exhibitions or Temporary Business Activities within the Territory Article 8

In the case that the Regulations herein come into force in the middle of a year, the standard for the amount of money stipulated in Paragraph 2, Article 3 shall be in proportion to the enforcement months of a year.
中文原文 外國之事業機關團體組織在中華民國境內從事參加展覽或臨時商務活動申請退還加值型營業稅實施辦法第8條
本辦法於年度中施行者,第三條第二項之一定金額標準,該年度按施行月份數占十二月份之比例計算之。

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