Why is the FLASHBACK file showing the previous days data after I ran an EXPUTIL BACKUP with the RESET option?
The Flashback file is a wrap-around file. When this file is full, new records overwrite the oldest ones. The RESET option is not valid for the FLASHBACK file.
If you log performance data to both an archive file and a flashback file, you should not need to back up the flashback file. If you log data to only the FLASHBACK file, you should regularly back up this file.