Xr battery life?

Hi, I'm trying to figure out whether battery life I'm getting on my new Xr seems fair.

I've read and seen screenshots of people getting up to 11 hours of screen on time with mid use.

Others an average of 8h sot between charges ( charging every other day ).

I'm currently charging every other day, however I'm only getting up to 4h sot total between charges.

I have background apps disabled, wifi and mobile on, voice notations and hey siri disabled, bluetooth disabled, auto brightness on although it mostly stays at 40%.

I noticed standby and idle seems great, but battery starts dropping quickly as soon as i launch any app.

Here are my findings:

Charge 3, outdoors:

Day 1 and 2: 4hours sot total and the screen between 20% and 70% brightness throughout with average at 33%, with airplane mode on occasionally. I did take lots of pictures and videos on the second day to be honest.

Charge 4, at work, limited use of the phone:

Day1: down to 75% and 2h sot, although I haven't used any app, no youtube, no camera, one phone call, wifi and limited exposition to mobile data.

Day2 (ongoing): down to 58% and 1h20mins sot, no apps, very limited use, no phonecalls, wifi.

At this stage I'm considering, just for the sake of being safe rather than sorry, to have it replaced as it's within the first 14 days of purchase. Any thoughts?