I suspect that the B1G is targeting 20 as the number it wants to be at. Assuming the XII is the conference that folds, this outline would jump the B1G from 14 programs today to 15) Missouri, 16) Kansas, 17) Oklahoma, 18) U Texas, 19) UConn (I hope), and one TBD slot for 20.
I used to think it was 20 as well, but I now think the magic number is a big question mark. If the ACC plan of eliminating the requirement of everyone within a division playing each other gets voted in, it would make scheduling much easier. With a lowered requirement for a CCG, there are numerous ways this could go. A simple way would be bringing in four schools. Let's say that The Big10 brings in UConn, Kansas, Oklahoma, and eastern school (VT, just as a plugin). They could play six divisional opponents and three crossovers.
Divisions would be ( Bolded teams are the three anchors)
East: UConn, Indiana, UMD,
Michigan, MSU,
OSU,
PSU, Rutgers, VT
West: Illinois, Iowa, Kansas, Minnesota,
Nebraska, Northwestern,
Oklahoma, Purdue,
Wisconsin
Michigan's 9 game conference schedule might look like this:
Divisional -
OSU, MSU, UConn, Maryland, Indiana, Rutgers (not playing PSU, VT)
Crossover -
Oklahoma, Minnesota (gotta have the game for The Little Brown Jug) and Illinois
UConn's might look like this:
Divisional -
PSU, Rutgers, VT, MSU,
Michigan, Indiana (Not playing OSU, Maryland)
Crossover - Iowa,
Nebraska, Northwestern
(I don't think The Big10 has a chance at UT and Mizzou, but the above four are the best candidates that would want to come to the Big10 if they could).