[GAMEPLAY] Rengar's Q gives extra atack speed

when playing rengar in the jungle noticed that, whenver i activate my Q it would give me atack speed (approximately 0.27) with no scaling on lvl or any other item(s). The atack speed boost wears off at the first auto atack or after about 2 seconds (in or out of combat); I dont quite notice a difference on the auto atack speed but i would like to point this out either way, however, i do have to point out that it can be used to atack turrets and it CAN be stacked. i apologize if the fact that i had to get the screenshots off from a custom game due to time issues i did my best to get as many screenshots as possible

1. activate Q (activating anything before does NOT affect in any way)
2. apply a Q on any kind of enemie (applying any other spells,actives or summoners after or before does not seem to affect either)
3. once the atack speed boost its active auto atack anything (as said above it wears off in about 2 seconds or so if nothing is hit)
4. if wishing to stack activate empowered Q, then Q again (with 45% CDR it seems to be almost permanent as long as you have something to hit)

i tried this in 2 ranked games and 1 custom game