Why did Lamson sell his Drillers stake?

Chuck Lamson, majority owner of the Tulsa Drillers since 2006, has sold his ownership shares back to longtime owner Went Hubbard. Hubbard owned the team from 1986 to 2006, retained a minority interest after selling to Lamson, and now has sole ownership once again. Lamson played for the Drillers in the late '70s, began working in the front office while still a player, and made his way up the ladder, serving a decade as general manager before taking over as owner.

Hubbard's previous tenure as sole owner was marked by almost annual improvements in old Driller Stadium: expanding seating, re-angling the seating along the foul lines toward the infield, replacing the original artificial turf with real grass, lowering the box seats nearer to field level, improving concession stands and locker rooms, adding a party suite, picnic area, and a new front office. Driller Stadium was (still is) a great facility for minor league baseball. In 1986 Hubbard took over a new but very incomplete ballpark, turning it into a gem. Now he has a facility that has every convenience and luxury already built in.

I have yet to see a reason given for Lamson's decision to sell. The quotes in the KWGS story hint at reluctance to leave:

"I knew this day would eventually come, but it has arrived a little quicker than I imagined. It is a bittersweet day for me as I have loved my 30-plus years with the Drillers, but I am excited about the new challenges that await me...."

"This change allows me to pursue new opportunities, but more importantly, it insures a positive future for the Drillers...."

Was he forced out? Was he in over his head financially? Anyone have a clue? It all seems rather sudden and strange.

MORE: Here's an item from the Gloucester County (N.J.) Times from a couple of months ago about Lamson's induction into the Woodbury High School Hall of Fame. The story, which covers his impressive high school and junior college pitching career, the injury that stopped him from reaching the majors, and his rise from Drillers groundskeeper to president, adds the detail that he was a 51% owner of the Drillers. As of October, he was in no hurry to move on:

Although Lamson has enjoyed immense overall success in Tulsa, he's in no hurry to make a move.

"I've had opportunities, but nothing has piqued my interest," he says. "With our new ball park, our future is secure. And I love Tulsa."