Quoted from Softpedia, shows its seriousness in providing upgrades to some of the Z series Xperia, Xperia ZL and ZR Xperia, Sony even has updated the product page at Xperia Blog for all the mobile phone, add a caption "May 2014" as the release period to upgrade the platform KitKat Android OS v 4.4.2 for the Xperia series.
Unfortunately, the Sony does not provide specific information about the release date of the update, so it looks like users will have to wait a few more weeks to receive the following information, or it could even reach the end of May 2014. Likely, Sony will make an official announcement of the availability of the release of the new platform as soon as it is ready roll-out, so that users ie Z Xperia series, the Xperia ZL and ZR Xperia can quickly install.
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