T-Mobile started distributing the June 2018 Android security update to all Galaxy S8 and Galaxy S8 Plus units on its network, with owners of Samsung's 2017 devices now being expected to receive the new firmware in the coming days, according to the wireless carrier's official support pages. The package intended to land on the Galaxy S8 is identified by the build number G950USQU4CRE9, whereas the Galaxy S8 Plus will be updated with the software version G955USQU4CRE9. The two over-the-air files are similar in size, weighing in at 327.16MB and 323.63MB, respectively.
The official changelog detailing the update mentions stability improvements, performance enhancements, and bug fixes, but doesn't elaborate on the matter. The Bellevue, Washington-based mobile service provider began the rollout on Sunday, less than a month since it started updating all Galaxy S8 and Galaxy S8 Plus models on its network with the May patch. While the 2017 series is receiving security patches in a relatively timely manner, at least on T-Mobile, the Galaxy S9 family that succeeded it isn't, with that state of affairs generating major criticism of Samsung in recent weeks. All Galaxy S and Galaxy A-series offerings from the South Korean company are eligible for monthly patches but Samsung doesn't guarantee that level of support and is largely dependent on its carrier partners to issue new firmware in a timely manner.
The Galaxy S8 and Galaxy S8 Plus are widely estimated to be some of Samsung's most successful handsets released this decade, with the Galaxy S9 lineup not being expected to surpass their commercial performance. Besides price cuts, Samsung recently resolved to attempt keeping the 2017 series relevant by refreshing it with a new Burgundy Red color which initially debuted in its home country this past winter but is now making its way to more markets around the world, having most recently launched in India.