def METHOD_NAME(
    mocked_notify, site_settings, customer_user, channel_PLN
):
    old_email = "example@example.com"
    notifications.send_user_change_email_notification(
        old_email, customer_user, get_plugins_manager(), channel_slug=channel_PLN.slug
    )
    expected_payload = {
        "user": get_default_user_payload(customer_user),
        "recipient_email": old_email,
        "channel_slug": channel_PLN.slug,
        "old_email": old_email,
        "new_email": customer_user.email,
        **get_site_context_payload(site_settings.site),
    }
    mocked_notify.assert_called_once_with(
        UserNotifyEvent.ACCOUNT_CHANGE_EMAIL_CONFIRM,
        payload=expected_payload,
        channel_slug=channel_PLN.slug,
    )