<xs:attribute name="OffsetDropTime" use="optional">
    <xs:annotation>
        <xs:documentation xml:lang="en">An enumerated type indicating when the deadline drop time goes into effect.</xs:documentation>
    </xs:annotation>
    <xs:simpleType>
        <xs:restriction base="xs:NMTOKEN">
            <xs:enumeration value="BeforeArrival" />
            <xs:enumeration value="AfterBooking" />
            <xs:enumeration value="AfterConfirmation">
                <xs:annotation>
                    <xs:documentation xml:lang="en">The deadline information applies from when the reservation was confirmed.  In some systems the confirmation time will differ from the booking time.</xs:documentation>
                </xs:annotation>
            </xs:enumeration>
        </xs:restriction>
    </xs:simpleType>
</xs:attribute>