T-Mobile has pushed July security update for the Samsung Galaxy S6 and S6 Edge smartphones via OTA in a phased manner. To install the update, you should be running the latest version of the relevant updates.
The update to Samsung Galaxy S6 is being rolled out as G920TUVS5FQG1. However, you should install the build number G920TUVU5FQE1 before attempting to install the July security update.
When it comes to the Samsung Galaxy S6 Edge, you need to install the previous version with software version G925TUVS5FQG1 to install the latest update G925TUVU5FQE1.
As the name suggests, the July update ships with security bug fixes and improvements although the official T-Mobile support page states as the security update.
If you are working with the above smartphones, you should install the update since it addresses important security vulnerabilities. The update also provides fixes to various bugs reported by the customers. After the installation of the update, you can expect an improved performance of your device.
Like in the case of all the previous updates, it will take few days for the update to hit your smartphones via OTA. You can also manually verify the presence of the update by navigating to Settings icon. You should also establish connectivity with Wi-Fi and charge the handset up to 90 percent.