Update: thank you everyone! user @Today has provided a great link of a discussion that suggests the correct answer is where being an abbreviation of, whereas as a replacement of since, hypothesized in these comments.
As I love archaic definitions, I’m more convinced to now that this is the answer!
Especially since the question originates from one weirdo using “where” instead of since.
https://english.stackexchange.com/questions/338694/is-it-ever-appropriate-to-use-where-instead-of-because-or-since
Like “Where we knew he was heading to Chicago tomorrow, we got on the first plane heading east to intercept.”
“Where we knew where the safe was, we began to cut through the wall in the corner behind her desk.”
Thanks
I have never heard this having married a Nutmegger (CT) from them or their family. I’ve actually never heard this from anyone ever in my life! The way I’m reading it, I can for some reason only hear it in a heavy Southern drawl, like MS or AL? ¯\_(ツ)_/¯
Removed by mod