Kayn's E interactions with turrets

So I have done about an hour of testing in the Practice tool as Kayn the newest champion to come to the rift and found some interesting interactions with his E and Enemy turrets.

A turrets range is a full circle, obviously, even spanning INTO the walls of the rift, but there is a weird interaction going on here, if Kayn starts OUTSIDE of turrets range and only ever goes in to turrets range that is also INSIDE terrain, he wont get hit. But if he ever gets targeted by the turret, even the terrain isn't safe until your next e cast.

TLDR: Think of it as this, the turret will NOT attack you in terrain unless you were previously targeted by the same turret IN THE SAME E CAST.

The Nexus has yet to be tested if it is able to protect you from both of the base turrets......if anyone would like to test this and post their results that would be great!!!