By Jake Trotter, Staff Writer, jtrotter@opubco.com Modified: June 11, 2010 at 9:41 am •  Published: June 11, 2010

The Big 12's end of days are at hand.

The last two days, Colorado and Nebraska launched their exit strategies.

Now, it's up to Oklahoma and Oklahoma State to formulate theirs.

Colorado became the first school to leave the Big 12, announcing Thursday it had agreed to join the Pac-10.

Next will be Nebraska, expected to declare today it's bolting for the Big Ten.

Despite a Kansas City TV station report that Texas and Texas A&M are going to the Big Ten, and OU the SEC, multiple sources continue to maintain to The Oklahoman the Sooners and Cowboys are Pac-10-bound, along with Texas, Texas A&M, Texas Tech and Colorado.

OU and OSU must begin to explore how to get out of the Big 12 and how much it will cost — a process that could become both complicated and litigious.

According to the league's handbook, Big 12 schools must give two years' notice and forfeit 50 percent of their conference revenue if they intend to leave.

Those buyouts increase if schools leave within the two-year window. That shouldn't be an issue, since Pac-10 commissioner Larry Scott declared during a press conference Thursday that competition in an expanded Pac-10 wouldn't begin until 2012.