Default Xperia ZU KitKat update begins!!

"The first device to get it is apparently the C6833 LTE model in Hong Kong. The new firmware is available only over the air for now, but we expect Sony to launch it soon via its PC Companion. We also hope other markets will be joining Hong Kong soon enough."

Source: http://www.ubergizmo.com/2014/03/and...-ultra-owners/

Edit: Lol that news's source is XDA itself
http://forum.xda-developers.com/show....php?t=2670991