How do I disable auto-turn-on Bluetooth after rebooting iPhone? Using iPhone 7+, iOS 11.1. Every time I reboot my phone, my Bluetooth automatically is turned on. This is NOT wanted and very annoying. I only use it with my remote shutter button when using my cam, which is rarely. How do I disable the auto-turn-on? 

p.s. I obviously know how to turn it back off via control center. But the point is I shouldn’t have to turn it back off, and back off, and back off, and...you get my point.
To stop the automatic enabling of Bluetooth on reboot, you must go to Settings > Bluetooth and shut off the Bluetooth radio completely.

Control Center is but a command for our convenience, not ultimate control.

I just tested this three times on my iPhone 7 running iOS 11.1.