In a strange turn of events, the Samsung Galaxy S3 on the T-Mobile network has updated to Android 4.3 Jelly Bean, one day after the T-Mobile Galaxy S4 was expected to update to Jelly Bean but didn’t.

T-Mobile announced the Galaxy S3 Android 4.3 update on its support forum on Tuesday. Amid all the issues that have surrounded the Android 4.3 rollout on other Galaxy S3 models and other Samsung Galaxy devices, the update is quite a surprise to many.

Most believed the T-Mobile Galaxy S3 would not update any time soon after the Sprint and AT&T models failed to update when they were expected. Soon it came to light that several Samsung Galaxy models were experiencing bugs and other post-update issues after receiving Android 4.3. Samsung stated that it was investigating the matter and had suspended the Android 4.3 update for international Galaxy S3 models, but has not commented on the update schedule for the Sprint and AT&T Galaxy S3 models.

Meanwhile, news has also spread about several Galaxy S4 models having experienced post-update issues after receiving Android 4.3, to the point where system updates have been postponed for both the AT&T and U.S. Cellular Galaxy S4 models. As said, the T-Mobile Galaxy S4 was expected to update on Monday and still hasn’t. A T-Mobile representative told IBTimes on Monday that there is also no indication of the Android 4.3 update being available for the network’s Galaxy S4 at this time. This makes it all the more strange that the Galaxy S3 has now updated to Android 4.3; however, another T-Mobile representative told us the network is often not aware of Android updates until just before they release. Notably the Android 4.3 update for the T-Mobile Galaxy was approved for the model just one day prior to its release.

The Android 4.3 Jelly Bean update for the T-Mobile Galaxy S3 includes such features as Samsung KNOX and Samsung Galaxy Gear support. The 486 MB T999TUVUEMJC build firmware is available over the air and through Samsung Kies. In order to update, T-Mobile Galaxy S3 handsets are required to be not rooted and running the T999UVDMD5 build firmware. The handset must have at least 50 percent battery life and the latest version of Kies for PC or MAC if using that method, or a stable data connection if updating over the air. The Android 4.3 update probably will roll out onto T-Mobile Galaxy S3 handsets in phases; those who have not yet received the update should get it in the coming days. Users can also check for the update manually by accessing Settings > About phone> Software update menu.

Users should keep in mind that the software update is optional. It is currently not known whether the issues that have occurred on other Galaxy S3 models persist on the T-Mobile Galaxy S3 model.

With the curveball of the Android 4.3 update for the T-Mobile Galaxy S3 now being available, there is no telling when Galaxy models, which haven’t updated or have had their updates halted will finally receive Android 4.3. It is likely that the leaked Android 4.3 rollout timeline, on which many have been depending, is not as reliable as before. However, the one prospective rollout date was Nov. 25 for the T-Mobile Galaxy S3 LTE model; the model that recently updated was the original HSPA+ model. It will be interesting to see when the T-Mobile Galaxy S3 LTE model actually updates. According to T-Mobile, it will do so soon.

Are you surprised to see the T-Mobile Galaxy S3 update to Android 4.3 Jelly Bean? Let us know in the comments below.

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