Fullwidth easy slider: setting first titel to H1, others to H2.

I found below code to place in the functions.php file to change h2 tags in the Fullwidth easy slider:to h1. However, now I have several h1 tags, which I don’t want either. I’m looking for a way to set the first titel to h1, the others to h2. how do I do this?

*Change h2 tag full width slider to h1
*/
function replace_tags_with_tags(){
?>
<script>
  (function($) {       
      function replaceElementTag(targetSelector, newTagString) {
        $(targetSelector).each(function(){
          var newElem = $(newTagString, {html: $(this).html()});
          $.each(this.attributes, function() {
            newElem.attr(this.name, this.value);
          });
          $(this).replaceWith(newElem);
        });
      }
    
      replaceElementTag('.slideshow_caption h2.avia-caption-title', '<h1></h1>');
    
  }(jQuery)); 
</script>
<?php
}
add_action('wp_footer', 'replace_tags_with_tags');