I have no luck unlocking my 820 either from ATT or third party unlock services. This is a cut from my recent discussion with ATT CSR:
E R: Hello! My name is E.R and I am an International Care Representative. I?m reading your inquiry and I will be right with you.
E R: I will be happy to assist you with your inquiry.
E R: May I please have the account holder's full name and the last four digits of the account holder's social security number?
E R: Thank you, allow me a moment to take a look at your account.
E R: There is no unlock code for this device. AT this moment, this device can not be unlock. I apologize for any inconvenience this may have caused you.
D M: When will unlock code be available for this device if you know?
E R: The unlock date just passed 05/09/2013.
D M: in other words, unlock code should be available for this device, but for some reason it could be not found?
E R: We will not be able to unlock your device at this moment. This device is currently exclusive only to AT&T.
E R: Hello! My name is E.R and I am an International Care Representative. I?m reading your inquiry and I will be right with you.
E R: I will be happy to assist you with your inquiry.
E R: May I please have the account holder's full name and the last four digits of the account holder's social security number?
E R: Thank you, allow me a moment to take a look at your account.
E R: There is no unlock code for this device. AT this moment, this device can not be unlock. I apologize for any inconvenience this may have caused you.
D M: When will unlock code be available for this device if you know?
E R: The unlock date just passed 05/09/2013.
D M: in other words, unlock code should be available for this device, but for some reason it could be not found?
E R: We will not be able to unlock your device at this moment. This device is currently exclusive only to AT&T.