It's in certification for the EYE experience update, which is the one you're asking for.
Android L is in 0 - evaluation.
If you click on "view full android update process" it brings you here:
Which explains the stages.
I think HTC is messing with my mind. Last night, the above link clearly pointed to the HTC One M8 update page and offered a device selection drop down and today it points to M7 and i cant select carrier devices?