Default 4.4 in may

update arriving in may
have a look at this
http://www.phonesreview.co.uk/2014/0...e-to-commence/

and a recent news from carrier sfr CHECK IT OUT GUYS
http://www.gsmarena.com/carrier_sfr_...-news-7939.php
xperia z ultra gets 4.4 we are not far

http://www.gsmarena.com/sony_xperia_...-news-7989.php

Xperia Z1, Z1 Compact and Z Ultra KitKat updates now rolling out, says Sony http://www.androidcentral.com/xperia...-out-says-sony
sony announces kitkat update schedule
http://www.gsmarena.com/sony_announc...-news-8075.php
one more news:
http://www.gsmarena.com/kitkat_updat...-news-8306.php
update seen:
http://www.phonesreview.co.uk/2014/0...2-update-seen/
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