Version: 3.3 New feature Changed characteristics of an existing feature (including a mechanism for indicating a change of the unique identifier) Withdrawn feature The version of the AIXM-Update.xsd schema to which the message conforms The effective date and time of the update The originator (source) of the message A sequential number (unique for all AIXM-Update messages issued by the same originator) The date and time when the message was created The date and time when the message was created