Change logging directory/file for an Upstart service
The cookbook says --logdir is a command-line option, which means it's not an option that goes into an upstart job file, but on the command-line of Upstart itself. You can verify this in the init(8) manual page, cf. http://manpages.ubuntu.com/manpages/precise/man8/init.8.html
--logdir directory
Write job output log files to a directory other than
/var/log/upstart.
In other words, it's a global option, not a per-job option.