Currently if a full backup is not taken or is unsuccessful before switching to synthetic fulls, it will skip the synthetic full jobs until the full is run successfully. This behavior causes problems for monitoring since errors are not generated and ticketing systems do not realize there is a problem until you go to restore the data.
Instead of skipping synthetic jobs that do not have a full backup to work off of, Netbackup should produce a job with a failure code to alert the admin team that there is an issue with the synthetic job. This will allow us to investigate the issue and will make us aware that there is an issue.