You can use bppolicynew command to rename an existing NetBackup policy. For details please read the NetBackup 5.1 Command Reference/Guide for UNIX (http://support.veritas.com/docs/268116).
There may be software and hardware compression taking place. This may be why you are seeing the difference in the amount of data on the tapes.
Even though the tape only states that it has 430 gig of data on the tape it still could be full. You...