There was a poster in the RF I believe who compared the last few TN hires.
Butch was (officially) hired on December 7, 2012. I can't remember when news begin to break but it was fairly close.
Lane Kiffin was (officially) hired on December 1, 2008, but news began to leak on November 28.
Dooley was an exception due to the circumstances so we'll ignore him (in more ways than one?).
For both Butch and Kiffin, the previous head coach was fired prior to the end of the season (though Fulmer stayed on until the end). This case seems to be most similar to Kiffin. I believe the Butch timeline was longer than hoped due to him being way down the priority list. The one variable we don't have historical data on is the early signing period. However, I still believe that an 11/28 hire (next Tues) would be in-line with previous hires.
Yes, you can argue "a new regime in charge," but I think the principles still stay roughly the same. I would speculate any leaks to start earliest on Friday 11/24 but more likely Monday 11/27 with the official announcement on 11/28. Many (potential) insiders have alluded to that day being significant. I think it logically makes sense. I wouldn't expect to hear anything this week.