And the last ones to be added before these recent 2 was the Arkansas and S Carolina additions in 1991. So back before then it was 10 schools with 6 in 3 states and 4 in their own state.
Go back even further and Tulane was also a member from 1932 - 1966 and Georgia Tech from 1932 - 1964. As well as Sewanee: The University of the South from 1932 - 1940.
So when the conference originated it was as follows
3 TN
2 MS
2 AL
2 GA
2 LA
1 FL
1 KY
It seems to be a growing trend for them but is barely able to be considered a rule or model...