Here the reply I received
Dear Patrick,
Thank you for contacting the Sony Xperia support centre.
We are sorry to hear you have not received the latest android update 4.4 Kittkatt for your Sony Xperia Z1.
We can confirm you may already have the latest software, depending on the date of purchase. Software updates are released at different times depending on operator and/or country. Therefore, we cannot give you an exact date for when a specific update will be available for your device.
Android version: Google Android 4.4 (Kitkat)
Latest available software: 14.3.A.0.757
Release started: 2014-04-10
To find your device’s current software version:
Settings > About phone > Build number / version
This upgrade for your Xperia smartphone includes many improvements, such as:
Introducing Android 4.4.2 KitKat with many new features and enhancements
Updated Camera application and overall tuning to improve the camera experience
Enhanced email app
Stability, performance & battery improvements
We hope this helps
This doesn't really help much as I know there was a bug fix for the current version I have months ago which was jellybeans and I haven't even had that