As a commenter below ... and Reuters ... notes:
David Stainton, president of Paramount Animation, resigned on Wednesday for personal reasons.
Stainton joined the fledgling animation unit in October after 17 years at Disney, where he once served as president of its feature animation division. ...
Mr. Stainton was on board for five months. As a development artist who had worked with Mr. Stainton at Disney said to me recently:
"I can't figure out why Viacom would hire Stainton to do their feature work in the first place. I was never impressed with him when we were both at Disney. When he left for the Paris studio I was happy to see him go ..."
Mr. Stainton started at Disney Features in development, moved to the Mouse's Paris studio, then returned to head up DisneyToon Studios and ultimately, the feature division. He stepped down when Robert Iger brought in Ed Catmull and John Lasseter to head up the division, but had an office in the Frank Wells Building until (presumably) the end of his Diz Co. contract.
His quick departure comes as a surprise. Perhaps he did leave for personal reasons, and we've got the dynamics wrong. But less than half a year? That's a remarkably short tenure.