[Request] Source for FSN acronym

[Rubo]

Hi guys, this request may be a little tricky: do you know if there exists even a single official source which states the acronym "FSN"? We already know about FGO, but FSN? (and if you have it, FHA too). Thank you!

[SilverBullet1317]

Is probably not official but just fan acronym, in interviews with Nasu they always refer FSN as "stay night", and FHA is just "Hollow".
Also from what I have seen, in Japan fans tends to leaves out the F, so when referring to FSN is only SN, FHA is just HAbor "Hollow" like how Nasu calls it, or even "HoloAta"(ホロアタ). The chinese fans are the one tends to use this format with the F a whole lot more… from what I have seen.