NPCs only affect the PIDRNG, which determines nature, gender, shininess, ability, etc. Not IVs.
Are you asking if that's possible? It's perfectly possible to get a non-frame 1 spread, do your advances, and find where you ended up, as long as there's no NPCs, and you take the same path every time.
Are you asking if that's possible? It's perfectly possible to get a non-frame 1 spread, do your advances, and find where you ended up, as long as there's no NPCs, and you take the same path every time.