How to get the actions to send newsletter with Trigger

I've been trying to send a simplenews newsletter using the scheduler module to 'publish' the newsletter. I have simplenews_action module turned on, and created a trigger to send pending newsletters with cron. What I was hoping is that a newsletter would become pending when the scheduler 'published' the newsletter, and then cron would send it.

What I have found is that cron goes ahead and sends an unpublished newsletter as soon as it runs. The newsletter is still unpublished! Is there a way to tell simplenews a newsletter only is pending and should be sent if it is published?

I need some advice on how to get a newsletter to be sent on a schedule!