So I read this question, where it says:
the only exception being Jubstacheit, who is supposed to be an A.I. controlling an array of humanoid golem bodies.
I've never read this before, so I looked it up on Jubstacheit's Wikia page, where it says:
Jubastacheit is an artificial intelligence made to control the Einzbern Castle, Golem Jubstacheit (ゴーレム・ユーブスタクハイト, Gōremu Yūbusutakuhaito?). It manufactures humanoid golem terminals, and Acht is the eighth generation.
However, this was not the case as on June 11, 2015, the same paragraph said:
Declared the eighth head of the Einzbern family, Jubstacheit was not around during Justeaze Lizrich von Einzbern's era, but kept himself alive for nearly two centuries by continuously prolonging his life.
This part started to change on January 13, 2016, and this new information had not been cited, as the only reference on the page is the Fate/Zero Season 1 Boxset - Drama CD 1, which has been there for quite some time.
So I am wondering, what Nasuverse title/material book says that Jubstacheit is an A.I?