Conversation so far:
What was the timeslot the Jay Leno Show was in?
Premiering on NBC on September 14, 2009, The Jay Leno Show aired on weeknights at 10:00 p.m. ET/PT9:00 p.m. CT through February 9, 2010.
What other show was the Jay Leno Show timeslot dispute over?
The Tonight Show with Conan O'Brien was other show in the Jay Leno Show timeslot dispute.

Question: When did the dispute happen?
Self-contained rewrite: When did The Tonight Show and Jay Leno Show dispute happen?