Nimbus cloak triggering after respawn if Ahri dies without using all three charges of her ult.

In a couple games now, I've had Nimbus cloak triggering randomly while my ult is on cooldown. One time I noted in particular it was after I'd died without using all three charges of my ult. This happened in both a summoner's rift game (normals) and a Howling Abyss game (ARAM). Dying without using all the charges might not be the cause, but that's what I noticed at the time. It may have been a coincidence, but, either way, I had the move speed buff trigger while my ult was on cd, and the nimbus cloak itself went on cooldown.