The 40￠ postage stamps of the Hongkong Martyr Print, then in stock, were converted into postage-due stamps with the characters〝欠資〞(postage-due) overprinted in Square characters at the bottom and the characters〝臺幣〞(Taiwan currency) overprinted vertically on the right side. The altered value in Chinese characters appears also in a vertical line on the left side and in Arabic figures in the lower two corners. The overprint was done by the Central Engraving & Printing Works, Taipei.