Running backups manually seems to cause issues
It appears that running backups manually as the
sympl user will cause the sympl-sqldump script to fail (as it's not running as root), possibly causing later backups to fail as a dump was started but not completed.
Sympl should probably check for a generic user with full mysql access rather than just root (or the root or Sympl user), and/or automatically use the
--force flag when triggering backups.