Ziggs Ult Cooldown Timer [Gameplay]

So, Just played reworked Ziggs in ranked game (OCE, sorry no OCE bug report page) and I ulted just as I died and the ult went through damaging all Champions within it. But I noticed when I re-spawned it did not have the CD timer on it. I tried to ult again but it wouldn't let me. So I figure it's just not showing the CD on it, and 1 minute later it works properly.

I do not know exactly how to reproduce the bug, but it most likely is dying at the exact moment you threw your ult. (Sorry can't go into more detail, Replay system crashed)