NOTICE ADVISORY TO GALILEO USERS (NAGU) 2013011 DATE GENERATED (UTC): 2013-09-10 15:15 NAGU TYPE: GENERAL NAGU NUMBER: 2013011 NAGU SUBJECT: UNVAILABILITY DUE TO SYSTEM UPGRADE EVENT DESCRIPTION: FROM 2013-09-11 UNTIL 2013-10-16 ALL GALILEO SATELLITES WILL BE EITHER NOT TRANSMITTING OR BROADCASTING DUMMY NAVIGATION MESSAGE