I just like to share my experience with battery drain in both JVK and JVB and give you a possible fix.
I experienced battery drain both in jvk and jvb and when you go setting - battery check, I would see high android OS - up to 60 percent which just drank the juice out of my phone.
I've decided to test all the apps, deleting one by one in order to locate which app was causing this problem and I found it to be "software update".
So here is a possible fix for you guys who are experiencing similar problem.
Go to setting - manage apps - all apps - find software update - delete data
In both JVK and JVB it solved my battery drain problem almost instanly.
I also did battery recalibration but doubt it played any part.
I hope above method will solve the battery drain problem.
does anyone know what exactly software update does?
and how to delete it completely off the phone.
I doubt I will be using OTA update or anything like that since I'm a big fan of odin.