Sony is now rolling out a new software update 43.0.A.7.55 for Xperia L1 smartphone. The update comes with Android April security patch.
The latest Android April security patch brings fixes for Common Vulnerabilities and Exposures (CVE) in the open-source Android OS. In addition, the firmware update also includes bug fixes and other improvements.
Software update 43.0.A.7.55 for Xperia L1 smartphone will gradually roll out to everyone. You can also check manually for updates, go to Settings > About device > System update.
Make sure you have enough charge on your device at least 60% to 70% before downloading the update.