The purpose of the amendment was to ensure that those who have to defer their parental leave or who are directed to return to duty can have their eligibility window for parental benefits extended. Military personnel do not have a choice; they have to obey. The purpose of the bill was to extend the period that individuals are eligible for parental benefits in cases where they cannot receive parental leave for reasons beyond their control.
On May 26th, 2010. See this statement in context.