DB plan distribution miscalculation

[pcbenefits007]

So, there is a DB plan that made distributions in Jan-Feb this year. After review, the plan sponsor realized they miscalculated the amounts and the participants are now owed more money (ranging from $77-$5000). Do they need to get new beneficiary forms completed since they're outside 180 days?

[Andy the Actuary]

Technically, a lawyer question. However, assuming you're talking about lump sums, is there any reason to believe that a participant or spouse would not have given consent for lump sum distribution if lump sum had been greater?