Way to confirm images on media to be manually expired are already duplicated successfully

Our backup is set up to to go to VTL first and then to physical tapes via SLP. Unfortunately the volume pool with 60 day retention on VTL is getting full and we are backlogged on duplications for about 60TB. I am trying to manually expire the media in the volume pool to free up the space for upcoming large number of backups. I can use bpmedialist to find media on VTL volume pool that will expire soon and expire those first. But how do I quickly ensure the images on those media are already duplicated to physical tapes successfully?

Thank you!