Sony officially confirmed that is going to release Android 4.3 for Sony Xperia SP (hopefully won't change their mind), but when will it come I belive is still unknown, at least to me. See this link for details: http://blogs.sonymobile.com/2013/07/25/on-android-jelly-bean-4-3/
there is no android 4.2 update for sony sp. it is directly updated to 4.3. I think it is going to be released in october last week or in november i dont know it for sure because there is no official info on android 4.3 update release date
