Conversation so far:
Where did the theorist Judith Butler study?
Judith Butler attended Bennington College before transferring to Yale University.
Where did Judith Butler go to college?
Judith Butler attended Bennington College.
When did Judith Butler graduate from Bennington College?
Judith Butler attended Bennington College before transferring to Yale University.
Did Judith Butler go on to graduate school after Yale University?
Judith Butler spent one academic year at Heidelberg University as a Fulbright Scholar.

Question: When did she graduate from Yale?
Self-contained rewrite: When did Judith Butler graduate from Yale?