Here is a description from espn.com that does state what you are saying 45. In most years, the 5+7 format will assure the conference champions from the SEC, Big Ten, Big 12 and ACC a spot in the playoff, along with the highest-ranked Group of 5 conference champion. The CFP intentionally won't refer to the Group of 5 in its description of the format, though, because there is a chance that a champion from one of the Power 4 conferences finishes ranked below the top champion from the American Athletic Conference, Conference USA, Mountain West, Sun Belt or Mid-American Conference.
In 2021, for example, when undefeated No. 4 Cincinnati was the American Athletic Conference champion, ACC champion Pitt finished at No. 12 with two losses. In the 12-team format, the four highest-ranked conference champions will receive a first-round bye.