If an ineligible spouse or an EP becomes a member of an eligible couple, any amount
                  of the couple’s benefit already paid to one member for a month of eligible couple
                  status, we pay on behalf of the couple.
               
               If for a past month a member received more than their “share” (usually one-half) of
                  the couple's benefit, retroactive adjustment is not required as long as the total
                  benefit paid to the couple is correct. If the total benefit paid is not correct, we
                  recalculate the amounts paid to both members to compute an overpayment or underpayment.