Mike has been covering college hoops in Philly for a long time, so I would trust his sources on this one:

Lange is an assistant coach on Brett Brown’s staff and this year took over the defensive duties vacated by Lloyd Pierce, who left for Atlanta at the end of last season. He’s been with Brown since 2013 after spending two years as Jay Wright’s #2 in Villanova.

Lange is a Philly-area native, having graduated from Bishop Eustace Prep School and Rowan University. He coached the Naval Academy from 2004 to 2011 and the U.S. Merchant Marine Academy from 1999-2001, in addition to serving as an assistant with Nova (2001 to 2004), La Salle (1998-1999), and Philadelphia (1996-1998).

The timing of this isn’t great, with the playoffs approaching for the Sixers. We can ask Brett about it tomorrow before the Nets game.