However, on Thursday the space agency announced it was rearranging their scheduled line-ups and Epps would be replaced by Serena Auñón-Chancellor for the June mission. The space agency hasn't released any information about why Epps was benched from her planned mission, saying only that "these decisions are personnel matters for which NASA doesn’t provide information," according to NASA spokesperson Brandi Dean. Epps will now work in the Astronaut Office at Johnson Space Center and await another possible flight assignment.  The brother of a Syracuse-born astronaut said "oppressive racism and misogyny in NASA" is behind the administration's choice not to send Dr. Jeanette Epps to the International Space Station. Epps, a Le Moyne College graduate, was part of NASA 20th astronaut class, announced in 2009. It was not clear from Epps' post whether he had spoken to his sister about why she was removed from the mission. So, he made that comment and I said, 'Wow, that would be so cool.'"
– Jeanette Epps was to make history when she set foot on the International Space Station in June, as the first African-American astronaut to do so. Emphasis on "was." NASA on Thursday announced a shake-up to its crew assignments, stating Serena Auñón-Chancellor would be bumped from her scheduled Expedition 58/59 to Expedition 56/57, where she would take Epps' place. Instead of Epps flipping to the later mission, she'll "return to NASA’s Johnson Space Center in Houston to assume duties in the Astronaut Office and be considered for assignment to future missions," and Anne McClain will join the Expedition 58/59 crew. Newsweek reports that NASA doesn't elaborate on "personnel matters," but notes someone is floating a theory. "My sister Dr. Jeannette Epps has been fighting against oppressive racism and misogynist in NASA and now they are holding her back and allowing a Caucasian Astronaut to take her place!" brother Henry Epps posted on Facebook on Saturday. Mashable notes it's hardly unprecedented for an astronaut to be pulled from a mission, and outlines the reasons that have surfaced in past instances, including medical issues. A former NASA administrator tells Syracuse.com that the likelihood is high Epps will make it to space. "When [crew changes] do happen, the reassigned astronauts almost always fly on a later mission. The exceptions are very few and far between." Sean O'Keefe further speculates that Auñón-Chancellor's medical background might be better suited to the mission's human research experiments than Epps, who is an engineer. (An astronaut who made history died last month.)