How to set up a date field based scheduled newsletter with Simplenews? On my Drupal 7 site I have on the one hand a news letter set up with the module Simplenews. On the other hand I have a content type with a date field. Now I would like the newsletter being scheduled by the date field. To be more precise:

The news letter should work as a reminder. Two days before the date saved in one of the date fields the news letter should be send.

How would that be possible. Actually I think, this does not work with rules, as there is not any triggering event, that could generate scheduled rule.
You could schedule a rule when the content type with the date field is generated.  You'd need to create a rule component that sends the email you want.  Schedule the component on content creation with the date field as the execution time.  

I'm using this mechanism to delay some heartbeat activities on my site.  Works a treat.