When I monitor my backups with the following query:
SELECT command, percent_complete, 'elapsed' = total_elapsed_time / 60000.0, 'remaining' = estimated_completion_time / 60000.0 FROM sys.dm_exec_requests WHERE command like 'BACKUP%' or command like 'RESTORE%'
I notice that before the backup, SQL Server perform a restore headeronly then the backup.
I was wondering what was the use for it and if its execution time could be reduced somehow. It appears to take longer than the actual backup.