The SEC has distributed the divisional rotation matchups for 2014 through 2025:http://msn.foxsports.com/south/story/se ... ons-051914
The conferences moved fast in settling the matter for an extended period. There was the grumbling from some of the usual complainers about having it tougher than some others, but the design looks intended to be basically fair. Sure the assigned permanent cross-overs have notable differences in distance, strength, and levels of intensity, but everybody has to have one in the 6-1-1 format. And marquee games that are permanent cross-overs were sought to be protected.
If the SEC expands in membership before 2025, that will be a doozy incorporating new scheduling. However, the model is adaptive to modification, and if new additions would be one to the east division and one to the west division, they could end up canceling the rotation with the other division entirely if 8 conference games would continue to be the limit. Or, they can then embrace the 9 conference game format, and maintain a rotation.
Also, in a situation whereby a new addition (such as FSU if it ever happens) that would already be a permanent OOC fixture on a member's schedule, and placement pertains to the same division, certain scheduling could be comparatively easier in some regards. That's part of why when it comes to scheduling, in-footprint additions should not be totally ruled out. For now though, the thinking about what schools could be added, suggests desirable major schools from states contiguous to the SEC, and no more than one from any new state that would be represented. That really narrows the any potential pool.
From what I hear about Mizzou, they seem content with being in the SEC-east. The Alabama schools have refused to split before, and seemed adamant to stay together in the SEC-west. Certainly whatever west school could be added may shape Mizzou's, and perhaps another's, divisional preference.
Future SEC expansion: NCSU to the east? Some current B12 school to the west? Whatever the case, how SEC divisions and scheduling currently exist, may largely determine who, how, and when, expansion candidates are determined if the issue gets back on the table at some future point. Maybe holding off on going to 9 conference games factors into the thought that future expansion is possible, and it may offer a bit more flexibility for future transitions. That said, there are multiple reasons for the consensus on the model adapted.