We cannot use the
.db.old file as when
.db generation is complete we would have outdated advisories. We cannot know if the cronjob has finished generating the
.db file, so we just rely on a
.bak file that we delet when done.
Other scripts as centos 8 snapshots will try to use the
.bak file if existent, fallback to
.db if not, this way it will use the latest advisories.