Fiora Ult Bug

Fiora's ult states that you are untargetable while using it. If this is the case you should not be able to be caught by a WW ult or killed after you use ult (unless the enemies team has AoE damage or prior to ult you get hit by DoT). So by the discription of the ult I believe that it is a bug to be killed mid ult by a champion like trist without being E'd first or getting locked down by a ww and your ult going on CD. Either the discription needs to be changed to show this weakness and bring clarity to the champion or it needs to be fixed so that should you be killed mid ult by an attack that targeted you prior to you ulting then your ult should not go on CD or have a reduced CD (for fiora haters that seem to thing she is op already).