Snippet to display estimated delivery in different format (simple and date range, settings should be in date range ) on product page based on shipping class. Estimated Delivery Date Plugin for WooCommerce - https://www.pluginhive.com/product/estimated-delivery-date-plugin-woocommerce/

functions.php

/**
 * Snippet to display estimated delivery in different format (simple and date range, settings should be in date range ) on product page based on shipping class.
 * Created at : 13 July 2018
 * Updated at : 13 July 2018
 * PluginHive Plugins : https://www.pluginhive.com/plugins/
 * Gist Link : https://gist.github.com/xadapter/a3aebdd786e553056b49617cfea0cc8b
 */
 add_filter( 'woocommerce_get_availability', 'ph_change_estimated_delivery_style_based_on_shipping_class', 11, 2 );

 if( ! function_exists('ph_change_estimated_delivery_style_based_on_shipping_class') ) {
	 function ph_change_estimated_delivery_style_based_on_shipping_class( $stock_arr, $item ) {

		$product_page_text_without_date_tags 	= "Estimated delivery by";
		$date_seperator 						= '-';
		$shipping_class_arr 					= array('test','shoe');		// Shipping classes for which simple date has to be shown
		$estimated_delivery_date 				= 'lower';		// Accepted value lower or higher

		$shipping_class 		 	= $item->get_shipping_class();
		if( ! empty($shipping_class) && in_array( $shipping_class, $shipping_class_arr) && ! empty($stock_arr['availability']) ) {
			$exploded_text_arr 		= explode( $product_page_text_without_date_tags, $stock_arr['availability']);
			$new_estimated_delivery = $exploded_text_arr[0].$product_page_text_without_date_tags.' ';
			if( ! empty($exploded_text_arr[1]) ) {
				$exploded_text_arr 	= explode( "</small>", $exploded_text_arr[1]);
				$exploded_date 		= explode( $date_seperator, $exploded_text_arr[0] );
				$exploded_date 		= array_map( 'trim', $exploded_date);
				if( $estimated_delivery_date == "lower" && ! empty($exploded_date[0]) ) {
					$new_estimated_delivery .= $exploded_date[0]."</small>";
				}
				elseif( $estimated_delivery_date == "higher" && ! empty($exploded_date[0]) ){
					$new_estimated_delivery .= $exploded_date[1]."</small>";
				}

				if( ! empty($exploded_text_arr[1]) ) {
					$new_estimated_delivery .= $exploded_text_arr[1];
				}
				$stock_arr['availability'] = $new_estimated_delivery;
			}
		}
		return $stock_arr;
	 }
 }