The update weighs about 900MB and bumps the Android Nougat Xperias up to Android 8.0 Oreo and brings the February 2018 security patch level.
Android 8.0 Oreo has a lot of improvements like smart reminders and actions through Xperia Assist, context menus when you long-press on an app icon or select text, better performance and much more. Check out this video for an overview of what's new.
After update my xa1 plus. Volume button cnot work
Because Sony UI is simplicity and gorgeous, that guy don't know the theme can change the UI just giving negative comments.
May be next month. They are rolling out in phases. So, it could take even end of next month. Who knows