woocommerce-output-custom-post-meta-after-price.php

add_filter( 'woocommerce_get_price_html', 'sale_ends_banner', 100, 2 );

function sale_ends_banner( $price_html, $product ){
	$sales_price_to = get_post_meta( $product->id, '_sale_price_dates_to', true );
	if( $sales_price_to ){
		$date_less_day = date_sub( $date, date_interval_create_from_date_string( "1 day") );
		$formatted_date = date( 'l jS F', $date_less_day );
		return $price_html."<p>Hurry! Sale Ends ".$formatted_date."</p>" ;
	} else {
		return $price_html;
	}
}