I'm also having this problem. Is it possible to add the Jetpack sharing module on schedule posts?
I'm using a plugin called "Simple Calendar for WordPress" that adds an Events post type for WordPress. It shows upcoming scheduled events on the site.
The Jetpack sharing module only appears after the event reaches its publish date. As sugested on the post above, I tried adding the code
<?php echo sharing_display(); ?>
on the loop but it didn't work.