If you want Bluetooth turning off/on at a preset time, use the app IFTTT (If This Then That)
You search for "Turn bluetooth off at this time" and enter your Days you want it too happen, Time that you want it too turn off
Same as above for "On" in the morning
I set mine to turn off at 8pm and on at 5am (You can still override this if you need to use it). Just an added security if you forget too turn it off in the first place.
Also someone mention that the Google Pixel 3 had a huge bluetooth range.
Mine is a Razor phone and bluetooth is really short range (less than 1m)