Confusion over entitlement and benefits under the provision

The answer given does not address Justice Kagan's question satisfactorily. It is argued that the irrationality lies in losing 12 months if one decides not to take the one month and switch immediately. Chief Justice adds that the individual is entitled to both benefits due to additional tours of duty, but cannot receive them simultaneously. It is seen as unfair to lose the entitlement to the whole 9-11 due to serving a disabled period of time.