We have a very sad news for Sony Xperia SP owners - there will be no Android 4.4 Kit Kat firmware update for that smartphone.Sony Xperia SP C5302 / C5303 / C5306 / M35c has reached end of life time and Sony has decided to end software support for that smartphone.
Sony Xperia SP C5302 / C5303 / C5306 / M35c has been announced in March 2013 and Sony has released one major firmware update for that smartphone:
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and the Android 4.3 Jelly Bean firmware is the latest one. Latest available software is: 12.1.A.1.205. Don't worry, Sony Xperia SP C5302 / C5303 / C5306 / M35c just like most of Sony Ericsson / Sony phones is still supported in our Sony Ericsson Online Service and all firmware versions for that smartphone are available 
Source: Sony
