Vouchers Miles and More SEN upgrade vouchers can be used to upgrade on LH.
Only valid on flights operated by LH/LO/OS with LH/LO/OS flight numbers.
Valid in all booking classes other than S & W (intercontinental flights) and L & T (European flights).
Ticket must be issued in the paid class of service before an upgrade is issued; all of the segments for which you request an Upgrade must be first confirmed in their paid booking class.