I am getting that by being on wifi 85% of time. Uses less power than LTE. Second I stream a lot of Apple Music from cloud so numbers are higher as it registers as on time but screen is off. Check out the details below the Music times, shows screen on time as well as standby time with the scream off.
I have turned off items like background updates, automatic app updates, background notifications, screen motion. I do have transparency on as well as Siri including activation when phone is off. This does not appear to use too much juice and I find it way handy for random questions I ask it.
I am currently running another charge use cycle, this time using more on screen time and less music. I will post those results.
I did let the phone cycle down to self shutoff then Charged to 100% leaving charger on for an hour after reaching 100%. This loads battery to max allowed by charging program. Does NOT condition the battery. This is false info. It does however calibrate the software so the % readings use the full charge range. After that I did reboot the phone use the home and on/off button at same time. This cleans out any stray code still running that might suck power.
Last big thing is I don't have Facebook, Instagram apps. These have been shown to suck power big Time even when phone screen is off as radio is used several times a minute. If you are on LTE in low reception area and these calls are made, you can watch battery level drop rapidly and even phone get hot.
That's all I can think of at moment. Oh and I have screen set manual at about 20% unless I am outside. Auto screen level seems to use more power than setting manual. Which is easy from pull up menu.