It goes to 9 minutes from 8, since every single communication gadget will yell out that the sun has disappeared as reports come in from the other side of the earth.
Ok yeah you’d definitely want any story to have the sun disappear take place at night, with a full moon, possibly a large harvest moon for ambiance. The moon disappears and within minutes you’re bombarded with calls…
Earthshine from where? That's still reflected sunlight! Maybe a tiny amount of cityshine, but the light pollution from those same cities will far outshine that.
Like you said, artificial lighting. Technically you'd get some IR from the planet itself which could get converted to visible light but definitely not nearly enough to be noticeable. You'd also probably get about 3 seconds of real reflected sunlight before that also goes away.