Continuity mistake: In the episode where they are on strike, Oswald says he gets a job with Global Postal due to the Christmas season rush, but, he was already working for Global Postal in the previous episode.
Drew and Mr. Bell's Nephew - S1-E14
Continuity mistake: Chuck is being hired as a security guard, when he has already been the security guard throughout the entire season.
Answer: "That Thing You Don't" (s03e10). The gang forms their old band again for a talent contest. Lewis is on drums, Drew is on trumpet, Oswald is on trombone, Kate is lead singer.
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