if ( 1 === preg_match( '/^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2})(Z|((-|\+)\d{2}:\d{2}))$/', $time_string, $date_bits ) ) {
        $offset    = ! empty( $date_bits[7] ) ? iso8601_timezone_to_offset( $date_bits[7] ) : wc_timezone_offset();
        $timestamp = gmmktime( $date_bits[4], $date_bits[5], $date_bits[6], $date_bits[2], $date_bits[3], $date_bits[1] ) - $offset;
    } else {
        $timestamp = wc_string_to_timestamp( get_gmt_from_date( gmdate( 'Y-m-d H:i:s', wc_string_to_timestamp( $time_string ) ) ) );