Jayce Hammer Form "Lag Delay"

Hello, I just noticed a bug on Jayce. Whenever you switch from mercury cannon to hammer form there is a slight "lag" or delay that happens almost as if the game crashed for a slight second. It is a bit annoying since in some situations using flash immediately is not possible due to the delay. From hammer to mercury cannon is perfectly fine though, is just the transition from cannon to hammer that experiences the delay. I would like Riot to take a look at this since I love playing Jayce and this delay makes him perform poorly thanks.