The IRS said Wednesday another 900,000 of these supplemental payments have been sent out over the last two weeks, including some with official payment dates of Wednesday. All told, almost 7 million of these payments worth more than $9.1 billion have been distributed by the agency this year.  The “plus-ups” are for taxpayers who received their third-round stimulus check based on an outdated tax return. Having reduced income or additional dependents are among the reasons you might qualify for a bigger check. And fortunately for taxpayers, it doesn’t work the other way around: There is no “minus-down” payment that you owe the IRS if you had more income or fewer dependents.  The checks, authorized by the American Rescue Plan pandemic relief bill, paid up to $1,400 per person and per dependent, with amounts reduced for individuals with adjusted gross incomes of between $75,000 and $80,000. (Those income cutoffs were higher for heads of household and married couples filing jointly.) This latest batch of “plus-ups” was worth $1.6 billion, meaning the average value was more than $1,700.