Publishers do this every time a famous author dies or becomes incompetent (in the legal sense of the word). Go Set a Watchman was a very early draft of To Kill

Publishers do this every time a famous author dies or becomes incompetent (in the legal sense of the word). Go Set a Watchman was a very early draft of To Kill a Mockingbird but sold to the public as an uncovered sequel novel a short while after Harper Lee's sister Alice died.