I mean you could announce a hire today...or three weeks ago back when yall was first saying Gruden to UT was confirmed
Its what Gruden wants. He's respectful to other coaches and doesn't want his hire to overshadow the end of the season. Its the same reason why nobody ever announces the new coach until the season is over. Even if they already have him signed. Just look back to Urban Meyer and Ohio State in 2011 as proof. Meyer was out of football. 2 weeks before the regular season ended, the reports leaked that he signed with Ohio State. He denied it. So did Ohio State. 2 weeks later, the season ends and he's introduced as the new head coach.
Same thing happened here except there was no need for Tennessee or Gruden to deny a leaked report that they signed the deal.
I'm telling you its been a done deal since 11/15/17. He's been contacting coaches. A staff is being put together. He just didn't want to make it official with an announcement until the season ended. That is why news leaked today of a possible press conference on Sunday at Tennessee.