Since commit 34fc406, sleep delay needs to be specified with --sleep-delay. Trying to specify it with Delayed::Worker.sleep_delay = will just get overwritten in the constructor for Delayed::Worker.
The enclosed patch fixes the documentation.
Sleep delay not available via Delayed::Work.sleep_delay; needs to be …
…set from command line.
Setting sleep delay via Delayed::Worker.sleep_delay still works. --sleep-delay will override Delayed::Worker.sleep_delay for that run if both are given.