After you file

The number of qualifying children on line 30 of Schedule 8812 is not calculated by TurboTax. TurboTax uses the number that you entered on the screen shown in the screen shot below. The number on line 30 of Schedule 8812 has nothing to do with the number of children that you entered as dependents.

Line 30 on Schedule 8812 has nothing to do with line 30 on Form 1040, which is for the Recovery Rebate Credit.