Even though we are 'promoting' him to the senior list, it doesn't mean he is now a senior listed player.
He will just remain a rookie who is allowed to play in the team. When we come to delisting 3 players at the end of the year delisting Newton will only free up a rookie pick. (if the rookie list still exists)
Actually if the rookie list and the senior list merges into one will probably be the best thing for us, as we will be able to delist current rookies instead of current senior players.