Aurelion Sol bug on his W

Hi. my name is Adrian (ing: one handsome guy) and i want to report a bug on Aurelion Sol's W. I played a recent game with him and it has a short delay (like 0.5 sec) when the circles deal damage. I hit a champion with my W powered up and deal damage after 0.5 seconds, not when W actually hits.

Please check it out, and sorry that couldn't post a video. Greetings,

Adrian