Aurelion Sol Q questions

Hey my first post! (not sure if this was the right place to put it :S )
Anyway I was looking for some idea on how Aurelion Sols Q works.

As many people who play Aurelion know; you cannot instantly reactivate his q ability, it has a short wait time. To quote Phreak: "The star travels peacefully until either Aurelion sol reactivates the ability or the star breaks past his outer limit"

Does anyone know the minimum travel time? Also, thoughts on why it was added, it seems to be crippling against any high mobility champs. Looking at no-one ...

Finally... Players, myself included, would be grateful if the delay could be described on his ability description or at-least described briefly.

Thanks for taking the time to read :)