prefix_bulk_adjusted_items.php

<?php
/**
 * Ignore discount on first x items in bulk rule
 */
function prefix_bulk_adjusted_items( $quantity, $cart_item ) {
  $ignore = 1; // Update the value here to equal the number of items that will not get discounted
	return $quantity - $ignore;
}
add_filter( 'wcfad_bulk_adjusted_items', 'prefix_bulk_adjusted_items', 10, 2 );