Sony Xperia Z — Xperia Z5 line; Stamina Mode returns!

Hello There

I want to share my experience with the new update from Sony with the comeback of the battery saver called "Stamina Mode".
I updated my Z5 this morning and was happy to see that the Stamina Mode has returned. I immediately turned the Stamina Mode on, as the battery life of my Z5 isn't that great at all since the Marshmallow Update. Just as i turned it on, I noticed that the big + next to the battery, which has indicated the Stamina Mode in Lollipop, which you may know if you used a Xperia Device before, isn't there anymore. I went around the phone and noticed its "laggyness" and its abrupt reactions to the touches, no more animations. I went straight back to the Settings, and there it hit me. It's not the Stamina Mode anymore as we knew it in Lollipop with the "White List" of apps that can use Background data, and all the other optimizations and customability. It's just the normal Android battery saver with a extraordinary name. This really disappointed me.

Has anyone experienced this as well and will Sony give us the "normal" Stamina Mode back, as it was in Lollipop?
Hoping for resonse.