According to @LlabTooFer, the HTC insider who usually tweets pretty accurate rumors, the HTC One Android 4.4.2 update will be released for the international variants of the smartphone by the end of the February.
For what it’s worth the HTC One Google Play Edition already received the Android 4.4.2 KitKat update in December. @LlabTooFer’s tweet also talks about other devices that will receive Android 4.4.2 soon, therefore, besides the international HTC One owners, the HTC One Dual SIM, HTC One Mini, and HTC One Max, should also keep their eyes on the notification area for the system update message.
The same HTC insider also mentions that the international variant of the HTC One X will not be receiving the Android 4.4.2 update. The HTC One X is currently running Android 4.2.2 and it looks like one of the reasons why it was denied KitKat is related to the Tegra 3 processor powering it.
As for the aforementioned HTC One, HTC One Dual SIM, HTC One Mini, and HTC One Max, the Android 4.4.2 will arrive with Sense 5.5 and not Sense 6, the later one being expected to debut on the HTC One follow up, unofficially dubbed HTC One + or HTC One 2, and known internally as HTC M8.
It was also reported that the US variant of the HTC One will be receiving the Android 4.4.2 update by the end of January, which will come along with HTC’s latest Sense version, named Sense 5.5.