Autopost Not Working With Computer Generated Stories

I've developed a PHP program which auto-generates Joomla articles once a day using function $new_article = new ContentModelArticle();

Autopost to my Facebook channel does not happen when these articles are generated.

However if I unpublish and republish from the backend autopost works.

Is there some trigger which needs to be executed when I save my auto-generated article? Or maybe the JFBC plugin is in the wrong order?

Any help appreciated.

Alex, its given me a starting point but I'm now totally confused.

I'm using the save($data) function as in require_once (JPATH_ADMINISTRATOR.'/components/com_content/models/article.php');

In article.php onContentAfterSave is triggered after batch moves and copies but not after an article save. Obviously it is triggered if I save an article in the backend because JFCB autoposts OK. So now the mystery is where does that happen?

I can't find it in any of the controllers or the helpers or views.

Any ideas?

I can't find where the save function does onContentAfterSave.

This is my code. It saves the article but doesn't trigger onContentAfterSave, or at least if it does JBFC doesn't post to FB.

function PublishArticle ($title,$introtext,$today)
{
JPluginHelper::importPlugin('content');
$dispatcher = JEventDispatcher::getInstance();
$new_article = new ContentModelArticle();
$data = array(
'title' => $title,
'introtext' => $introtext,
'state' => 1,
'catid' => 20,
'created' => $today,
'created_by' => 68,
'language' => "en-GB",
'publish_up' => $today,
'access' => 1,
'featured' => 0,
'metadata' => array(
'robots' => "",
'author' => "",
),
);
if ($result = $new_article->save($data))
{
$dispatcher->trigger('onContentAfterSave', array('com_content.article', $result, true));
}
}