I was playing as Urgot earlier and the ult would channel for a second but then the position reverse wouldn't work, I would just be left standing there. I was playing with a friend, so we decided to do some testing (he was brand) if he landed the stun (after shooting it before I suppressed him, then I would be stunned and the ult would stop, which makes sense, but there were multiple times while his stun was on CD, and the ult would still fail. I'm not sure how to get the dxdiag (or whatever it's called) so I can't show you that, but how to repro it (specific to our situation, idk about anything else)

1. set up 1 v 1 on the proving grounds, Urgot vs Brand
2. Have the Urgot ult the Brand
-It should be noted that, at first, the ult was working perfectly fine, but as we got further and further into the game, it began to become less and less predictable until it finally stopped working altogether

I am unable to reproduce.

Worthy of note: It is possible for brand to cast his Q right before Urgots ultimate applies the supress effect. Due to travel time, this could potentially stun you out of your ultimate, before the position swap can occur(The timing required would be difficult to replicate, but still possible). Is it possible that brand stunned you out of your ult? or was this a consistent occurrence each time?

blazerboy what is your summoner name in PBE?