controlling notifications in job_Queue

it says in the README that using job_queue is recommemended:

"I recommend enabling the job_queue.module. When you do, group email notifications are sent during cron runs, instead of immediately after a post is submitted. This speeds up posting a lot, for big groups. The delay also helps authors fix typos in their posts before the mail is sent."

Is there a way to cancel the notification before the CRON job runs? I could not find an option to cancel the sending of messages for job_queue.