Dave Lyon with the 2013 GMC Acadia

Dave Lyon won't be taking over as head of design for Opel and Vauxhall after all. The Detroit Free Press reports the designer abruptly left General Motors last week for unknown reasons, just days before he was supposed to step into his new role. The defection is the latest in a string of management upsets at the two marques. Earlier this month, Opel CEO Karl-Friedrich Stracke departed to assume other duties within GM, opening the door for Steve Girsky to step into the role for the time being.

Lyon joined GM in 1990 and worked as the executive director of GM Asia Pacific design before transitioning to his post as head of North American interior design. He was instrumental in penning the cabin of the 2013 Cadillac XTS and the Chevrolet Volt. He also helped steer Buick toward greater design consistency with Opel. The new position would have made him vice president of design for GM Europe.