Kelvin bug with refresher ult and new cast

[Rex]

If Kelvin is currently ulting, uses refresher, and then (while looking at a target) tries to cancel the first ult, it will instantly cast the second ult. Pretty niche but can be match losing (as I just found out).
Also I'd love for a way to swap the alt cast around with frozen shelter, I'd much prefer to have the targeted version be the alt cast.