The records from the National Registration Act 1939 are available, although some details have been redacted:
The records created under the National Registration Act are held by The National Archives but were not freely accessible to the public for many years. From 2010, subject to restrictions to safeguard the privacy of people who are or may still be living, information could be obtained from the NHS Information Centre about specific individuals for a fee. The National Archives has now entered into an agreement under which the original documents for England and Wales have been digitised and scanned and are available (subject to privacy restrictions) on the subscription-based Findmypast and Ancestry.com websites. The digital images can also be viewed at The National Archives themselves in their reading room.
Per Ancestry.com, they are updating the records when people are over 100 years of age, or a death has been reported to their archives.