To update: Today, after 1hr of SOT, my phone has dropped 21% battery. All I've done is surf the Internet, reading websites (No streaming, videos, music, social media). So at rate like that, that works out at less than 5hr SOT, from full, for a phone that's less than 6mths old.
Update 2. This is the battery stats for today. I've not used the phone as I've been out cycling (hence the levelling out) BUT look at the drop in battery from when I was using phone. 😬