I just replied to another post that is along the same lines as this one. The concept of that you want to do is there. http://support.advancedcustomfields.com/forums/topic/radio-field-conditional-in-afc_form/
In the pre_save_post function to do 1 your would include code in the if
if( $post_id !== 'new_post' ) {
// change post status
return $post_id;
}