you can do via service center but i doubt the availability of latest firmware in service center. And flashing the latest firmware won't void your warranty because it's the official firmware Press Thanks if I helped you
As i'm the new user and my post counter is below 10 m not allowed to post links. by the way its no need to root ur device for flashing new firmware. If u want to use modified(tweaked & modified) your device must have root permission. check out the roms made by Cmahendra and geek-droid.Both are based on latest firmware.
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