Sejuani permafrost bug

occasionally (one every 10 or some games) when Sejuani casts her "E" on something with full stacks, the spell just... doesn't work. The stacks disappear, the ability goes on cooldown, there's no damage and no stun and no lockout period for more stacks to occur, they just start back over at 1. I have not been able to reproduce this intentionally yet, but it seems like it MIGHT be related to the enemy getting displaced or sejuani hitting it with an auto attack at JUST the right time. LUCKILY, so far--knock on wood--I've only had this occur vs an enemy CHAMPION once, and we still managed to secure the kill, but I've had it happen against jungle minions, ESPECIALLY rift scuttler, multiple times, so I wanted to make sure that someone at Riot was aware of it.

I'll update this post with a log, a video or how to reproduce it if I ever figure out how to do it on purpose.