Velkoz Ult Bug, no CD

Just played a game with velkoz where i ulted 2 times in a row without going on CD. After the 2nd ult the spell was still not on cool down and i could let again. The first two ults were back to back, firing 180 degrees the opposite direction. It occurred shortly after using the frost queen claim active and killing a target. I have no video to show, it, but will experiment in a custom.

Edit: The bug lets were full channel as well. Played one custom so far, nothing to show. I do not have time to experiment more at the current time.