Samsung The Galaxy S21 series is now receiving a new update (G99xBXXU1AUB6) and comes with the February 2021 security patch.
The changelog is not as descriptive and, like the update that came before it, it talks about improvements in overall performance, security and camera. Although Samsung does not say this explicitly, it appears that the update aims to address the power consumption issues caused by a recent update, as some users XDA Forums say you fixed these problems.
The issue was also recognized by Samsung and was considered working on a fix.
According to posts in Reddit and Samsung Community forums, the previous firmware update substantially affected battery life. Apparently, this was just an issue for the Galaxy S21 and S21 Plus with Exynos. Users reported that putting the phone in airplane mode fixed the problem, which implies that it had something to do with cellular connectivity.
The Snapdragon models and the Galaxy S21 Ultra powered by Exynos were not affected.
The new update is being released to users in the UK, Switzerland, Belgium and Germany, and is likely to reach more markets in the coming days. You can also check manually by navigating to Software Update in Settings and tapping Download and Install.