Anivia R bug, stopping Kassadin Q and Thresh E stopping it when Anivia has Banshees Veil

When you cast Anivia R it can be stopped by spells like Kassadin Q , but the ultimate gets also interrupted, if Anivia bought Banshees Veil. To reproduce the bug just buy banshees Veil with Anivia, cast R and cast Kassadin Q on Anivia, her R stops than. It Occured to me everytime when the above mentioned case happens. May be happening with all kind of cc.