Morgana`s ulti gets interrupted while under her shield

Hellaw,

I played a game with morgana recently and discovered a bug where when I used my ulti after I have shielded myself to become immune to magic (i was fighting vs lulu, tahm and ez), when lulu polymorphed me between 2 phases of my ulti, I didnt get polymorphed but my ulti was interrupted. Same happened later on in the same game with tahm's devour (I asked tahm to help me out test it). Im impying that morganas spell immune shield works pretty bugged, as the effect partly happens instead of completely disabling cc abilities. Devour still pulls target to tahm but he doesnt devour the target so it works 50%.

Please look into the all possible ccs in game and test them all against morganas sspell immune shield (focus on doing so between 2 ticks of her ulti as some of them might interrupt it as well)

Chers !

Vlad