HTC refreshed its Software Updates webpages with new information on the Android 4.4.2 and Sense 6 upgrade for HTC One Max and HTC One (M7) devices, informing that most variants are on the way to receive an upgrade.
We can read that AT&T HTC One (M7) received certification along with HTC One (M7) devices from Sprint, Verizon and also the Unlocked ones.The T-Mobile HTC One (M7) is in the development stage and Sprint and Verizon HTC One max devices is already being certified to receiving the Android 4.4.2 KitKat together with Sense 6.0 update.
The new firmware for AT&T HTC One Mini is still in the integration phase.
The Bell, Rogers, TELUS, SaskTel, Virgin Mobile, and Wind Canadian carriers completed the certification for their HTC One M7 devices to receive the Android 4.4.2 KitKat.
You can go and check for your HTC device status and also see a diagram of the full process on the HTC Software Updates webpage. You probably know that before reaching a user device the upgrade process requires some stages such as evaluation, development, integration, certification, in the end to be pushed to the customers.
So that being said we can assume that it is not so long to wait until we can enjoy the latest version of Android on our HTC devices.