New NFL rules on interviewing coaches on other teams (like an offensive coordinator), state that the hiring team can interview those coaches in the last two weeks of the season, as long as the head coach has been fired or has been told he won't be coming back. If you don't interview them in this window, you have to wait until that team is eliminated from the playoffs.
I assume the Wilfs be be looking at the hot OC candidates from playoff teams, so I look for Zim to know his fate after week 16. Monday Dec 27th is the new "Black Monday" in the NFL.