Is there a height requirement for how high up junction boxes are placed on vertical walls? I know they need to be "accessible" but is 8' high considered accessible (with a cover plate that's exposed from the drywall)?

I need to re-route wiring that was in a partition wall that we just removed. We are leaving an 8-10" header between my kitchen/living room and would like to put the junction box in the header (close to the ceiling but not ON the ceiling) so it's "out of sight". Is this OK?

Thanks!