Looks like we are nearing the official Android 4.1.1 Jelly bean update for the Samsungâ€™s T-mobile version of galaxy S3. Folks at sammobile have leaked another OTA update which is less buggy than the previously leaked Jelly bean update for the T-mobile S3.
You need to on latest ICS firmware with stock recovery installed to flash it. Download the OTA update from here. If you do not like the bugs associated with this leaked firmware, you can roll back to the ICS by following our â€˜roll back to ICS on t-mobile galaxy s3â€™ tutorial,related queries: t-mobile galaxy s3 jellybean OTA update