Texture 2D Array, Mips Streaming?

Hello,

I’ve been studying a way to use 2D texture array in my material (after being inspired by CD Project for what they did for The Witcher in “Blood and Wine”)
and after I’ve discovered that they can have mips but won’t be streaming. I know we can call them inside the material with compute mipmap level, but before doing that I’ve checked in Texture Streaming Accuracy, and it seems they are actually being streamed although in the Texture Editor it’s showing Not Streamed.
Could it be a bug? Or Am I doing something wrong?