When archiving files and using FSA the system does the process in 2 steps.
Step 1 it archives the files that correspond to your archiving policy. If this also has "remove safety copies after backup" then the last step will not happen until the backup has been completed.
Once the safety copy has been backed up, the 2nd step should occur on the next Archiving Run, this should convert the files to placeholders. If you read thru the Archiving reports in the Report folder on the EV server, you should see something like:-
ARCHIVE ReadyForArchive this is a report only mode
ARCHIVE Archived this has archived the file
ARCHIVE AwaitingBackup the scheduled archive has run BUT the DVS file has not been backed up
ARCHIVE MadePlaceholder placeholder has been created
So it kinda looks like this:-
Monday Scheduled Archive runs, archives the files, safety copies awaiting backup
Tuesday Scheduled Archive runs, DVS files not yet backed up, stay WaitingBackup - no placeholders created
Wednesday Backup runs, Scheduled Archive runs, Placeholders created
hope this helps!!
Mark