According to the Engadget, At&t version of HTC One will not be able get it's boot loader unlocked once it sees the official release(presumably April 19th). Although it was reported some users who had early access to the HTC One, it was affirmed by HTC to the Engadget.com that the AT&T version of HTC ONE will not be supported by the HTCdev unlock service. It may be blocked once it's released officially.:-[
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