Conversation so far:
What did Wally Schirra do in the Apollo program?
Wally Schirra was assigned to command a three-man Apollo crew
What did the three-man Apollo crew assigned to Wally Schirra do?
to make the second crewed flight test of the Apollo Command/Service Module, with a mission profile identical to Apollo 1
How did wally Schirra get involved with the Apollo program he was assigned to?
Grissom and his crew were killed in a fire during a test. Wally Schirra's crew became the prime crew of the first crewed flight.

Question: When did Schirra do the second manned flight test for the Apollo Command/Service Module?
Self-contained rewrite: When did Wally Schirra do the second manned flight test for the Apollo Command/Service Module?