たすくまの過去のメールを引っ張り出すGoogle Apps Script

main.js

function main() {
  wakeupTaskumaMail(nowMinusDate(7));
  wakeupTaskumaMail(nowMinusDate(30));
}

function wakeupTaskumaMail(date) {
  const query = "label:たすくま " + toYYYYMMDD(date);

  const threads = GmailApp.search(query);
  for (var i = 0; i < threads.length; i++) {
    const thread = threads[i];
    thread.markUnread();
    thread.moveToInbox();
  }
}

function toYYYYMMDD(dateObj) {
  const date = dateObj.getDate();
  const dateStr = (date >= 10) ? String(date) : "0" + String(date);

  const month = dateObj.getMonth() + 1;
  const monthStr = (month >= 10) ? String(month) : "0" + String(month);

  const yearStr = String(dateObj.getFullYear());

  return yearStr + monthStr + dateStr;
}

function nowMinusDate(num) {
  const date = new Date();
  date.setDate(date.getDate() - num);
  return date;
}

function nowMinusMonth(num) {
  const date = new Date();
  date.setMonth(date.getMonth() - num);
  return date;
}

1ヶ月前だと月末処理が面倒なので30日前にした。わざと曜日をずらしている。