Sprint has become the first carrier in the US to push Android 4.4.2 KitKat to the HTC One, following promises from HTC to have it out to all users by the end of January. 

The upgrade is available for download by Sprint customers, by accessing Settings -> About -> Software updates. On 11 February, Sprint will begin pushing out the update over-the-air to HTC One handsets.  

Verizon, T-Mobile, and AT&T are still in the certification phase before pushing out the update. HTC previously announced it would be missing its January deadline to have the software to all users. 

"We are currently in the certification phase across all of our carrier partners in North America, and they share our enthusiasm for getting this software in your hands," Jason Mackenzie, president of HTC's Americas unit, said in January. "That said, the software development process does not always follow a linear path and we know today that we will miss our self-imposed target. The good news is that we won’t miss by much."

There must be some sort of hiccup at the carriers to bring such a delay, but HTC doesn't think it will be much longer until the update is out. 

HTC has already begun to roll out the update in parts of Eastern Europe, Canada, Middle East and North Africa. There's no word on the UK, but it shouldn't be too far behind the US.