The October 2020 security patch is now rolling out to various Galaxy smartphones, including the Galaxy Note 10+ 5G on T-Mobile's network in the US. The Galaxy A50 was the first Samsung smartphone to get the new security patch. Later, the update was released to unlocked variants of the Galaxy S10, Galaxy S20, Galaxy Note 10, and the Galaxy Note 20 series.
The new update for the Galaxy Note 10+ 5G on T-Mobile's network carries firmware version N976USQS3CTI8. T-Mobile's official support page for the smartphone doesn't mention the changelog but expect the new software to also include bug fixes and stability improvements. The update started rolling out yesterday, and it would have reached your smartphone already.
In addition to Android's security vulnerabilities, the October 2020 security patch also fixes 21 Samsung-exclusive vulnerabilities. Last month, the carrier had rolled out the August 2020 security patch to the smartphone. It also enabled support for T-Mobile's standalone 5G network in the US, offering improved connectivity and range where there's 5G coverage.
If you are a Galaxy Note 10+ 5G user on T-Mobile's network in the US, and the update hasn't reached your phone yet, you can check for the update manually by navigating to Settings » Software update on your device and tapping on Download and install.
