The AOC Consortium began to audit the changes made to the users and services of the EACAT platform in mid-2010 . In this sense, it is possible that in the changes prior to these dates, the word Unknown appears as responsible for the modification made.
This data can also appear if the user who did the action has been deleted from the platform.
On the other hand, it is possible that the name of the person responsible for the change corresponds to some user of the AOC Consortium because we ourselves have taken some action related to that service or user.