How to use the moment-timezone.default.utc function in moment-timezone

const niceParameter = function (parameter) {
      switch (parameter) {
        case 'OZONE':
          return 'o3';
        case 'PM2.5':
          return 'pm25';
        default:
          return parameter.toLowerCase();
      }
    };

    // Get the measurements
    // Filename should be the current time in UTC like '2016030616' and then
    // get the previous hours measurements
    const dateString = moment.utc().subtract(1, 'hours').format('YYYYMMDDHH');
    const file = `HourlyData/${dateString}.dat`;
    const lineToObj = function (line) {
      return {
        aqsid: line[2],
        day: line[0],
        hour: line[1],
        location: line[3].trim(),
        timezoneOffset: Number(line[4]),
        parameter: niceParameter(line[5]),
        unit: niceUnit(line[6]),
        value: Number(line[7]),
        attribution: [{name: 'US EPA AirNow', url: 'http://www.airnow.gov/'}, {name: line[8].trim()}],
        averagingPeriod: {unit: 'hours', value: 1}
      };
    };
    getObjects(source.url, file, lineToObj, (err, measurements) => {

const getDate = (day, time, offset) => {
    // Grab date from page, add time string and convert to date
    const dateString = `${day} ${time}`;

    // A bit odd looking here based on what we're getting in the files
    const utc = moment.utc(dateString, 'MM/DD/YYYY HH:mm');
    const local = moment.utc(dateString, 'MM/DD/YYYY HH:mm').utcOffset(offset);

    return {utc: utc.toDate(), local: local.format()};
  };

const getDate = function (date, timezone) {
    // For offset, we're making use of the fact that moment.js picks up first string
    // like +02 in the provided url
    const mo = moment.utc(date, 'YYYY-MM-DD HH:mm:ss').utcOffset(timezone, true);

    return {utc: mo.toDate(), local: mo.format('YYYY-MM-DDTHH:mm:ssZ')};
  };

exports.fetchData = function (source, cb) {
  // Because we're getting the data async, make a top-level timeout
  // to keep things from going on forever. Default to 7 minutes
  const timeoutId = setTimeout(() => {
    return cb({message: 'Failure to receive data from EEA system.'});
  }, (process.env.EEA_GLOBAL_TIMEOUT || 360) * 1000);

  // Unsure of how date is exactly handled by the EEA system, the adapter
  // applies a generous buffer to the toDate and fromDate
  let fromDate = moment.utc().subtract(12, 'hour').format('YYYY-MM-DD+HH[%3A]mm');
  let toDate = moment.utc().add(1, 'hour').format('YYYY-MM-DD+HH[%3A]mm');

  // Only ask for the pollutants we want
  let pollutants = acceptableParameters.map((p) => {
    // https://github.com/openaq/openaq-fetch/issues/202
    if (p === 'pm25') { p = 'PM2.5'; }
    return p.toUpperCase();
  });
  pollutants = pollutants.join();
  let finalUrl = `http://fme.discomap.eea.europa.eu/fmedatastreaming/AirQuality/AirQualityUTDExport.fmw?FromDate=${fromDate}&ToDate=${toDate}&Countrycode=${source.country}&Pollutant=${pollutants}&Format=XML&UserToken=${process.env.EEA_TOKEN}&RunAsync=True`;

  request(finalUrl, function (err, res, body) {
    if (err || res.statusCode !== 200) {
      return cb({message: 'Failure to receive job ID from EEA.'});
    }

    // Since we're asking for the data asynchronously, keep checking for

const getDate = (day, time, offset) => {
    // Grab date from page, add time string and convert to date
    const dateString = `${day} ${time}`;

    // A bit odd looking here based on what we're getting in the files
    const utc = moment.utc(dateString, 'MM/DD/YYYY HH:mm');
    const local = moment.utc(dateString, 'MM/DD/YYYY HH:mm').utcOffset(offset);

    return {utc: utc.toDate(), local: local.format()};
  };

exports.fetchData = function (source, cb) {
  // Because we're getting the data async, make a top-level timeout
  // to keep things from going on forever. Default to 7 minutes
  const timeoutId = setTimeout(() => {
    return cb({message: 'Failure to receive data from EEA system.'});
  }, (process.env.EEA_GLOBAL_TIMEOUT || 360) * 1000);

  // Unsure of how date is exactly handled by the EEA system, the adapter
  // applies a generous buffer to the toDate and fromDate
  let fromDate = moment.utc().subtract(12, 'hour').format('YYYY-MM-DD+HH[%3A]mm');
  let toDate = moment.utc().add(1, 'hour').format('YYYY-MM-DD+HH[%3A]mm');

  // Only ask for the pollutants we want
  let pollutants = acceptableParameters.map((p) => {
    // https://github.com/openaq/openaq-fetch/issues/202
    if (p === 'pm25') { p = 'PM2.5'; }
    return p.toUpperCase();
  });
  pollutants = pollutants.join();
  let finalUrl = `http://fme.discomap.eea.europa.eu/fmedatastreaming/AirQuality/AirQualityUTDExport.fmw?FromDate=${fromDate}&ToDate=${toDate}&Countrycode=${source.country}&Pollutant=${pollutants}&Format=XML&UserToken=${process.env.EEA_TOKEN}&RunAsync=True`;

  request(finalUrl, function (err, res, body) {
    if (err || res.statusCode !== 200) {
      return cb({message: 'Failure to receive job ID from EEA.'});
    }