Is there any way to rebackup a logical log that has been marked as backed up?

We've been backing up logical logs to disk for some months using a modified version of Art Kagel's log_full.sh command. Its been going well, but I noticed that sometimes, if logical logs get marked as complete fast enough, some of the logs seem to drop into the bit bucket rather than go to disk. This may be due to my compressing the logical log in the script and somehow multiple copies of log_full.sh running simultaneously. I've fixed the problem by adding a lock file, but I appear to have missing backups. Any way to reback these up? Thanks in advance, Todd