Wyo. Stat. § 2-3-911: Treatment of underpayments or overpayments.

In the event of an underpayment to a beneficiary, the trustee shall pay to a beneficiary within a reasonable time, and in the event of an overpayment to a beneficiary, the trustee shall recover from the beneficiary either by repayment by the beneficiary or by withholding from future distributions to the beneficiary, an amount equal to the difference between the amount properly payable and the amount actually paid.