What does it mean when Duplicity exits with exit status 23?

I'm running Duplicity for backup of my desktop to a remote storage. Everything has been working fine, but now I see in my log that Duplicity has been exiting with exit status 23 for a couple of runs. As of what I can see the backups are running and the backups are uploaded to the remote computer. The exit status 23 seems to only happen when it's run in the background as a cron-job. When I run the backup script manually I get a 0 exit status. Duplicity's man page lacks info on the meanings of the programs exit statuses, so I don't really know where to start. cat syslog.1 outputs: ... Jan 23 12:54:35 xx anacron: Job `cron.daily' started Jan 23 12:54:35 xx anacron: Updated timestamp for job `cron.daily' to 2019-01-23 Jan 23 12:54:45 xx kernel: [ 322.467223] EXT4-fs (sdb1): warning: maximal mount count reached, running e2fsck is recommended Jan 23 12:54:45 xx kernel: [ 322.473997] EXT4-fs (sdb1): recovery complete Jan 23 12:54:45 xx kernel: [ 322.474404] EXT4-fs (sdb1): mounted filesystem with ordered data mode. Opts: (null) Jan 23 12:55:03 xx kernel: [ 340.754000] EXT4-fs (sdc): recovery complete Jan 23 12:55:03 xx kernel: [ 340.794089] EXT4-fs (sdc): mounted filesystem with ordered data mode. Opts: (null) ...