Does anything stand out in your Battery Stats that's shows large %'s of usage @Sa34
Can you screenshot that part of your phones settings and post it back here.
By putting your phone in Safe Mode which disables your downloaded apps and leaves the stock ones working this can help rule out if the issue is one or more of your downloaded apps if they haven't been fully optimised yet.
I've read that apps such as Clean Master can cause issues.
A person can send logs and feedback via the Samsung Members app / Samsung + App too.
As you've just completed a major update it can take a few days to settle on your phone.
Occasionally a back up and factory reset can help as a very last resort.
A Samsung Experience Store or Samsung Service Centre can run a diagnostic test on the phone too.