Urgot Q Mana Cost lower than it should be

As the title explains, Urgot's Q is lower mana cost than it should be. It used to cost 55 mana, now it costs 35 - 55 based on rank, although the tooltip doesn't say when you try to level it up. This is most likely an oversight from when Urgot got his Q mana cost decreased in one of the PBE iterations.