All signs have pointed to the imminent release of Android 4.4.3 Kitkat OS update as the latest firmware was seen in the Google Play Edition of Sony Xperia Z Ultra.

Android Geeks spotted a Sony Xperia Z Ultra GPE running with the a new software version labeled, "KTU72.S1.3013."

KTU72 is an Android 4.4.3-specific build. Except that the new update will arrive on most Nexus experience handsets, Bluetooth SIG listing doesn't offer more data about the new firmware.

This was not the first time the upcoming 4.4.3 version of Android Kitkat OS was seen in different devices. The different firmware builds were seen previously in Nexus 5 and Nexus 7.

Also, Android 4.4.3 update was also spotted in Play Store, after Google updated the changelog of the Edu Device Setup app. The What's New section of the Edu Device Setup noted after the new update it would have "support for Android 4.4.3 and non-Nexus tablets," which might indicate that the new update would be pushed to the users soon.

In the previous week, U.S. carrier Sprint announced it will roll out the Android 4.4.3 Kitkat OS update to its Nexus 5 handsets on April 21. Specifically, the KTU84F, also known as 4.4.3 version, was expected to roll out gradually from April 14 to 21 starting with Nexus 5. But the carrier announced recently that latest update will not roll out anytime soon.

"Important Note: Due to an issue with the software, this update has been put on hold. Will update this post as soon as the rollout resumes to Google Nexus 5 Software Update - KTU84F." This message was posted on Sprint's Web site.

Google has not revealed the official changelog of the Android 4.4.3 Kitkat OS update yet. But it was reported the OS update will bring fix to the bugs and issues found after installing the 4.4.2 version of Kitkat.

Also, the update was claimed to address Bluetooth and Wi-Fi connectivity issues, random reboots, USB debugging and VPN problems, among others. The latest update would bring bug fixes mostly and not bring any new features to the devices.