Looking good!
If you sand that down a bit before wiping & sanding in your next coat, it should only darken the grain a little (the lighter parts will remain that same colour).
It's only when you start to get so far that the whole lot starts to darken. Saying that, it does depend on what oil you're using. I used Danish with no tint.
once you're happy with the colour, leave it for a week or so to dry properly & then give it a coat of beeswax paste, leave for an hour or so & then buff it (or if you feel it needs more oil, sand it & oil). Leave for another couple of days & then add another coat of wax.
If you want to, you could also oil that neck. It's probably already oiled to stop the grain coming apart.