adding snapshot backups?

[lloyd]

currently, i have a backup schedule that uses ten tapes over ten days. 
however, i think this just provides one recent copy of a given file.

periodically, i'd like to create snapshots (full backups) in case 
someone has a corrupt file that went unnoticed since the last backup.

what's the best way to do this?  can i change my current config somehow, 
or should i create an additional config that runs the full backups?

thanks