Some of the pertinent portions of the reply from the Taiwan based firm says that HTC is developing unlocked bootloader software for the phone which is necessary because updates for many phones, including the HTC Sensation, were finalized before the change in policy. The manufacturer goes on to say that HTC Sensation owners should, "be assured that we are working on a solution for our customers and our commitment has not changed. Please stay tuned to our official channels for ongoing updates on how we will be implementing this policy. Thank you for your patience."
HTC still needs to clarify which of its previously released models will be unlocked, and when the policy will begin to take effect on newly launched models. As we told you, the HTC Sensation 4G will launch from T-Mobile on June 15th.
source: XDA-DevelopersForum via AndroidCentral