BUR #49010 has been approved by @evazion.
create implication fate/unpublished_material -> fate/stay_night
Fate/Unpublished Material is a booklet that contained unused plot elements and characters that were originally intended to appear in the 2006 Fate/Stay Night anime but did not make the final cut. It is where Tachie originated from. Since she is an unused character, it does not make sense that she would simply be from Fate/Stay Night.