At a time when Samsung is expected to release the Android 4.1 Jelly Bean update - the newest version of Google's mobile operating system - for its Galaxy S3 smartphone Aug. 29, it appears that owners of the T-Mobile version of the device can already try out the update, thanks to a leaked version of the OS.

Android Police reported Friday that a forum member on XDA-Developers posted an early OTA file for T-Mobile's Galaxy S3 (T999), which is claimed to bump up the device to Android 4.1.1. However, the report added that "the OTA (which carries build JRO03L) is not without its caveats" either.

According to the report, first time users, looking to flash the new build, will have to be running stock build T999UVALH2 initially. There are also chances of users losing root when applying the update.

On top of this, the build also seems to have some issues. For instance, Wi-Fi calling seems to be dysfunctional, bugs in the stock browser and the video player need to be fixed, Google Now may or may not work and some possible general performance issues or lag.

The Verge has said that the new Jelly Bean update for the Galaxy S3 is apparently similar to the existing Android 4.0 build, since it includes Samsung's usual TouchWiz treatment on top of Android.

Last week, another leaked build of the Jelly Bean for the Galaxy S3 (i9300) popped up on XDA, claiming to give users "the chance to test the first Jelly Bean ROM by Samsung."

SamMobile reported that it "received the first firmware for the Galaxy S3 based on Android 4.1.1 Jelly Bean" and shared a few visible changes that were found after installing the firmware (I9300XXDLG4) on the Galaxy S3. Take a look at the step-by-step guide here.

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