Framerate lag with Jayce

When Jayce swaps from cannon to hammer stance, a half second of fps lag is had across the map. Anywhere from 10-25 fps is dropped and then it goes back to normal. This bug only occurs when Jayce goes from Cannon TO hammer, not the other way around. 8/10 players in this game were affected. It seems to only happen on the Howling Abyss.