I see X89D on P.472-473 of LegCo file (Almost last pages).

According to Wikipedia, it consists of 89D, 89S and X89D, so I combine them in one route master. X89D doesn't have a wikidata.

https://zh.wikipedia.org/zh-hk/%E4%B9%9D%E9%BE%8D%E5%B7%B4%E5%A3%AB89D%E7%B7%9A


But in HKBus Fandom, 89D and X89D are independent articles. I would create another route master for X89D.