The news that all the other versions of the HTC One M7 will be denied Android 5.1 was posted on Twitter by HTC's Vice President of Product Management Mo Versi:

The rollout of the Android 5.0 Lollipop update began for the HTC One M7 earlier this year. It is now available for the Sprint, T-Mobile and C Spire versions of the phone, along with the developer and unlocked editions.

Source: Mo Versi (Twitter); Via: Android Police