Promote sticky to slider and limit number of slides

I have created a feature slider with the ultimate goal to be:
Display 5 recent posts using a custom field called “featured_article”
Allow a sticky post to be promoted to the slider while still maintaining only 5 total slides (4 featured and 1 sticky).

The slider works fine when there are only the featured_article posts. The problem, when a sticky post is first published, only 4 total slides show. It remains this way until 5 new featured_article are posts are live.

Let me know if you need more clarification.

[Moderator Note: Please post code & markup between backticks or use the code button. Your posted code may now have been damaged by the forum’s parser.]

<?php
$sticky = get_option( 'sticky_posts' );
// Count how many there are, if any
$count = count( $sticky );
if($count >= 1){$postsperpage = 4;}else{$postsperpage = 5;}
$args = array(
	'posts_per_page' => $postsperpage,
	'post_status' => 'publish',
	'meta_key' => 'featured_article',
	'post_in' => $sticky
    );
$featured = new WP_Query( $args );
?>

<section class="featured" id="featured-slider">
	<ul class="bxslider">
    <?php while( $featured->have_posts() ) : $featured->the_post(); ?>
	  <li id="post-<?php the_ID(); ?>" <?php if(is_sticky()) { echo "class='sponsored-main featured'"; }else{echo "class='featured'";}?>>
	  	  <figure style="position:relative; z-index: 1;"><a>"><?php echo get_the_post_thumbnail() ?></a></figure>
			<div class="slider-content">
				<h1 class="featured-title">
					<a>">
						<?php the_title(); ?>
					</a>
				</h1>
				<p><?php new_excerpt(150); ?></p>
			</div>

    <?php endwhile; wp_reset_query(); ?>

</section><!-- end slider -->

[Moderator Note: No bumping, thank you.]