Yesterday I flashed latest June patch system through odin. As a new firmware battery calibration is needed. I discharged my battery completely so that it not even turns on. For the 1st time in 7 months I really observed fast charging as it took just 2hrs 30min for 0-100% charge. In 7 months it never happened. Previously 0-80% used to take 2hrs and max 2hrs 16min. Remaining 20% takes around 40-60min. So overall 100% used to take nearly 3hrs 16min to 3hrs 30min and more sometimes. Hence I decided to charge upto 80 and between 20-80%.
In my previous post I mentioned WiFi issues as I have to turn off & on every 30min or less. I even tried hard reset which never fixed. But now it was gone. Getting good WiFi signals and stability. I flashed the rom yesterday around 5pm and after complete setup didn't turned off WiFi not even 1s still I'm getting stability and speed.
Note: After 10 update battery usage in device care is not clear so I used Accubattery app for all my tests.
Mesuraj if a update is available you can install it through smart switch through pc/laptop. It is said that smart switch app in pc scans files before installing it on mobile so that no corrupt files or any causes issues.