I haven't seen any calculator. I'm going by this:
https://www.secsports.com/fbtiebreaker
If Texas goes undefeated, that means:
The worst case scenario would then be:
The SEC says:
Alabama clearly would be #1 and in the CCG.
So now there's a three-way tie for #2 between Texas A&M, Ole Miss, and Texas.
Texas A&M vs. Ole Miss
A. Head-to-head competition among the tied teams (None)
B. Record versus all common Conference opponents among the tied teams (Tie, 5-0 vs. 5-0)
C. Record against highest (best) placed common Conference opponent in the Conference standings, and proceeding through the Conference standings among the tied teams (Tie)
D. Cumulative Conference winning percentage of all Conference opponents among the tied teams (Could go either way)
Texas vs. Texas A&M
A. Head-to-head competition among the tied teams (Fuck you aggy, Texas wins the tiebreaker)
Texas vs. Ole Miss
A. Head-to-head competition among the tied teams (None)
B. Record versus all common Conference opponents among the tied teams (Tie, 5-1 vs. 5-1)
C. Record against highest (best) placed common Conference opponent in the Conference standings, and proceeding through the Conference standings among the tied teams (Texas via Georgia)
Based on that, it would seem Texas would have the tiebreaker against both aggy and Ole Miss if all three teams wind up with just 1 conference loss.