https://www.ibtimes.co.uk/android-4-3-12-1-0-266-official-update-xperia-sp-c5303-released-1436078
Android 4.3 (12.1.A.0.266) Official Update For Xperia SP C5303 Released | IBTimes UK
Feb 12, 2014 - Sony released Android 4.3 Jelly Bean update for Xperia SP.