user: Question: When did Peter Butler leave his team?
Columns: ['Team', 'Outgoing manager', 'Date Outgoing', 'Reason of departure', 'Replaced by', 'Date of Replacement']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['PSIS Semarang', 'Edi Paryono', 'July 23, 2008', 'Sacked', 'Bambang Nurdiansyah', 'August 29, 2008']
SQL:

assistant: SELECT "Date Outgoing" FROM "Table" WHERE "Outgoing manager" = 'Peter Butler';