The device Xperia E1 (D2004 / D2005) produced by Japanese manufacturer Sony, runs Android 4.3 Jelly Bean operating system and is equipped with 4-inch WVGA display, 3.2 MP camera, dual-core Snapdragon processor clocked at 1.2 GHz 200, 512 MB RAM, 4 GB internal storage and battery capacity of 1750 mAh.
Now this device receives a small update from build number 20.0.A.1.12 to 20.0.A.1.21., according to xperiablog.The update file is received by OTA and measures just 13.1 MB, so is expected to fix bugs and improve the performance. To check manually for the update you can go in Settings -> About phone -> Software updates -> System updates.
For now, it is unknown whether the devices Xperia E1 dual, version 20.0.B.0.83 will receive an update, but be sure that as soon as it appears will let you know.