The two changes are the addition of the Boston Bowl and the Pool of Bowls arrangement. Just for fun, I took this year's bowls and current team assignments and tried to reconfigure them into the 2020 bowl setup. I tried to keep a tight geography. I don't pretend that this is anywhere close to being accurate.

Cotton Bowl: Memphis VS Penn State
Boston Bowl: Cincinnati VS Boston College (From Birmingham Bowl)
Military Bowl: Temple VS North Carolina
Birmingham Bowl: UCF VS BYU
Liberty Bowl: Navy VS Kansas State
Military Bowl: SMU VS Air Force
Boca Raton Bowl: Tulane vs FAU

In 2 of the last 5 years, PAC would not have a bowl eligible team for the new Los Angeles Bowl. So the MWC Champ might become available as an AAC bowl opponent now and then in the Pool of Bowls arrangement.

If BYU wants to play a ranked opponent in a bowl game, BYU will need to play an AAC ranked opponent.

The reverse is also true. If AAC wants to play a ranked opponent (other than NY6 Bowl), then the only possible teams available that could be ranked are BYU and Boise State.