According to unnamed government sources in: http://m.focustaiwan.tw/news/aeco/201811210022.aspx
the numbers 7,8 and 9 will replace the second letter in the ARC/APRC numbers to denote the cardholder’s gender, as male, female or transgender,
… that’s not going to work, right? Sites use the second number in their validation right now, and that will expect a 1 or 2