Google App Script, highlight new users since last month

Question

I made a little function to retrieve the users we have on Google Workspace, and made a cron for this list to be refreshed once a month.

What I'd like to do now is to highlight cells of the new users created last month, but I didn't find a proper way to do it yet.

ie. next execution planned will be the 1st of June, I would need all accounts created in May to be highlighted

Any hint ?

My current code looks like this :

function listAllUsers() {

 var sh = '-- my sheet id --';
 var sheet = SpreadsheetApp.openById(sh);
 var sheet1 = sheet.getSheetByName('sheet title');
  
  var sheet1range = sheet.getRange("A:H")
  sheet1range.clear()
 
  var data = [];
  data.push(['Email' ,'First Name', 'Last Name',  'Suspended', 'Last Login Time','Creation', '2FA Active', 'Is admin']);
  var pageToken, page;
  do {
    page = AdminDirectory.Users.list({
    
      domain: '-- my domain --',
      pageToken: pageToken
    });
    var users = page.users;
    if (users) {
      for (var i = 0; i < users.length; i++) {
        var user = users[i];
        data.push([user.primaryEmail, user.name.givenName, user.name.familyName, user.suspended, user.lastLoginTime , user.creationTime, user.isEnrolledIn2Sv, user.isAdmin ]);
      }
    } else {
    Logger.log('No users found.');
       }
    pageToken = page.nextPageToken;
  } while (pageToken);
  
  sheet1.getRange(1,1,data.length,data[0].length).setValues(data);
  var dated = sheet.getRange("P1")
  dated.setValue(Utilities.formatDate(new Date(),Session.getScriptTimeZone(),'dd-MMM-yyy'));
  
}