[GAMEPLAY] Strange Kalista Ultimate Delay/Bug

When I tell people about this glitch/bug, they think Vladimir was in his pool or something. So this is one of those bugs that you just have to see to believe, I used the client's 'highlight' feature to record a clip. This webm clip is playable in Firefox at webmshare with no need to download. This site in particular includes audio playback so feel free to turn the sound up

https://webmshare.com/play/B7QgM

As you can see in the clip here, I use the ult and it goes on cooldown however nothing happens for quite some time. My teammate Brand confirmed they heard the ult go off, I suspect everyone nearby on the map heard the audio cue as well. This is the first time I have seen this happen.