OK, this is what I would do. I would follow the suggested steps in the following technotes. I would not trust that the current version of 6.0 MP4 has actually fixed theses problems.
BUG REPORT: Schedules for active policies fail to start despite being due for backup.
When using Veritas NetBackup (tm) 6.0, it is possible that scheduled backups will not run if the frequency setting in the policy is set to less than one day. This could result in data loss. This issue is resolved by NetBackup 6.0 MP4 released on November 20, 2006.
AGAIN, I would ignore the part about this supposedly been fixed with MP4