One way to keep it from happening is take it all the way to the SB. There's plenty of examples where teams didnt want to wait that long to fill positions.
Then again, there could be well over 10 teams trying to hire HCs.
Would be terrible if JDR left. Fox has alot of influence on this defense though. McCoy leaves its almost certain Tom Moore is brought in for the final couple years left in Mannings career
The trend has and will be new HC blood. Not retreads. That's a plus in keeping JDR