function setCustomRunTriggers() {
  Utilities.sleep(5000);
  var sheet = SpreadsheetApp.getActiveSpreadsheet().getSheetByName("PushedSchoolHolidays");
  var nextMidnight = sheet.getRange('D3').getValue();
  var nextSeven = sheet.getRange('D4').getValue();
  var nextSevenOFive = sheet.getRange('D5').getValue();
  var type =  getType(nextMidnight);
  while (type!="Object") {
    nextMidnight = sheet.getRange('D3').getValue();
    nextSeven = sheet.getRange('D4').getValue();
    nextSevenOFive = sheet.getRange('D5').getValue();
    type =  getType(nextMidnight);
  }
  var triggers = ScriptApp.getScriptTriggers();
  for (var i = 0; i<triggers.length; i++) {
    var eventType = triggers[i].getEventType();
    var triggerSource = triggers[i].getTriggerSource();
    var handlerFunction = triggers[i].getHandlerFunction();
    if ((handlerFunction=='functionA')&&(eventType=="CLOCK")&&(triggerSource=="CLOCK")) {
      ScriptApp.deleteTrigger(triggers[i]);
    }
    if ((handlerFunction=='functionB')&&(eventType=="CLOCK")&&(triggerSource=="CLOCK")) {
      ScriptApp.deleteTrigger(triggers[i]);
    }
     if ((handlerFunction=='setCustomRunTriggers')&&(eventType=="CLOCK")&&(triggerSource=="CLOCK")) {
      ScriptApp.deleteTrigger(triggers[i]);
    }
  }
  ScriptApp.newTrigger('functionA').timeBased().at(nextMidnight).create();
  ScriptApp.newTrigger('functionB').timeBased().at(nextSeven).create();
  ScriptApp.newTrigger('setCustomRunTriggers').timeBased().at(nextSevenOFive).create();
}

try{
    ScriptApp.newTrigger('myFunction').timeBased().after(10000).create();
  } catch(error){
    MailApp.sendEmail("[email protected]", "NEWTRIGGER FAILED!", "Creating new time based trigger failed: rn" + error);
  }