Short answers, pulled from the story.
NASA publicly announced six new astronauts from Group 4 on the 29th of June 1965. This announcement marked a shift in selection criteria away from test pilot experience toward doctorates in natural sciences or engineering.
Members of NASA Astronaut Group 4 held doctorates in natural sciences or engineering instead of test pilot experience. The National Academy of Sciences conducted initial screening of applicants who submitted transcripts by the 31st of December 1964 before reducing the pool to fifteen individuals for medical exams.
Harrison H. Schmitt became the twelfth person to walk on the lunar surface during December 1972 as part of Apollo 17. He joined the prime crew of that mission on the 13th of August 1971, which served as the final crewed landing on the Moon.
Duane E. Graveline resigned after his wife filed for divorce on the 18th of August 1965. She accused him of violent outbursts that threatened NASA's public image leading to his departure from the program.
A total of 1,351 applications arrived at the deadline for review by the 31st of December 1964. About 200 candidates were rejected immediately for failing basic age, citizenship, height, or vision criteria before moving forward to academic qualification checks.