It appeared that autotrack information is being purged. I am no longer able to retrieve autotrack data from last week or any previous weeks. Please advise if this can be changed.
In $AUTOSYS/bin/DBMaint file the "archive_events -A -l" option defines the number of days of "autotrack logs" kept in your AutoSys database.
Beyond this period the autotrack logs are archived in "archived_audit*" files under $AUTOUSER/archive directory.
So the solution is to consult the information in the archive_audit* files you can find under $AUTOUSER/archive directory.