public static function _update_tax_rate_postcodes( $tax_rate_id, $postcodes ) {
		if ( ! is_array( $postcodes ) ) {
			$postcodes = explode( ';', $postcodes );
		}
		// No normalization - postcodes are matched against both normal and formatted versions to support wildcards.
		foreach ( $postcodes as $key => $postcode ) {
			$postcodes[ $key ] = strtoupper( trim( str_replace( chr( 226 ) . chr( 128 ) . chr( 166 ), '...', $postcode ) ) );
		}
		self::update_tax_rate_locations( $tax_rate_id, array_diff( array_filter( $postcodes ), array( '*' ) ), 'postcode' );
	}