Of course, there's nothing to stop the CFP selection committee from ranking BYU differently than the AP and Coaches Polls. So, it could happen that the CFP rankings put us at #13, while the AP and Coaches Poll ranks us much higher.
But, the final CFP rankings directly determines who plays in the NY6 bowls, after all of the conference bowl contracts are satisfied and any displaced champions and the top G5 champion have been identified.