I actually didn't want to make a whole new post about just this small issue but I don't see it fitting anywhere else so..
It seems like before patch 6.1 it was already hard to find a spot on the operators to backstab, but it was doable by some weird positioning. Yesterday, however, it seemed downright impossible to find his 'back'. Pretty much tried running around the fella and standing inside the red circle (any position) but it seemed that the Operators don't have a backside anymore while channeling. Anyone else experienced the same problem? Or was it just me? In that case it was either a one time bug or I'm a bit retarded.