Well, your first post did mention letting the milk cool first (step 2a). I personally don’t see why you can’t start in a jar, then put the jar in cold water to cool it, then add the yoghurt, and go from there.
But well, to each his/her own. 
Well, your first post did mention letting the milk cool first (step 2a). I personally don’t see why you can’t start in a jar, then put the jar in cold water to cool it, then add the yoghurt, and go from there.
But well, to each his/her own.