[Gameplay] Xayah Ulti stays Untargetable after Zoe Sleep

While playing Zoe I hit a Xayah with my E. It landed and before Xayah slept she ultied finishing the animation but sleeping in the air and staying untargetable. I feel like she should land or cancel the ulti if she is forced to sleep mid cast.

I wonder if this can be recreated with Vlad poll and Fizz E if the target sleeps and stays in the untargetable mode longer then the spell says.

Can watch video to see what is being talked about