Addon: silverstripe-australia / memberprofiles — add HeaderField

Silverstripe Version:
3.7

Question:
Using the addon silverstripe-australia / memberprofiles. I am adding many member profile fields, and would like to have header fields in the member signup form to create more understandable groups o fields. As noted in the docs, I have created an extension MemberExtension.php with additional fields. TextField and TextAreaField are displayed, however HeaderField is ignored. Is there a way to add a HeaderField?

<?php

class MemberExtension extends DataExtension {

  private static $db = array(
    'PrimaryPhoneNumber' => 'Varchar(64)',
    'SecondaryPhoneNumber' => 'Varchar(64)',
 //...
  );

  public function updateMemberFormFields(FieldList $fields) {

    $fields->push(new HeaderField('NewLabel', 'New Label'));
    $fields->push(new TextField('PrimaryPhoneNumber', 'Primary Phone number'));
    $fields->push(new TextField('SecondaryPhoneNumber', 'Secondary Phone number'));
//...
    }
}