That looks like it came from the 2021 edition of Pub 17, for use in preparing 2020 returns.  On the 2021 Form 1040, the amount of the Recovery Rebate Credit will be based on 2021 information.  The ARP legislation in March 2021 had some language expressing Congressional hope that IRS would figure out a way to avoid double dipping, but I don't think that has happened.  They do make you pay it back if you received ACTC for someone not a dependent in 2021.