iOS bug wrt UITableViewSource that overrides EstimatedHeight

gistfile1.cs

public class Source : UITableViewSource
{
    public Source(UITableView tableView)
    {
        // because of a call to ReloadData here...
        tableView.ReloadData();
    }

    // ...this won't be called...
    public override nint NumberOfSections(UITableView tableView)
    {
        return 0;
    }

    // ...but this will be (even though we want to have 0 sections)...
    public override nfloat GetHeightForHeader(UITableView tableView, nint section)
    {
        throw new NotImplementedException();
    }

    // ...but commenting out this overload fixes the problem, even though this overload is also not called!
    public override nfloat EstimatedHeight(UITableView tableView, NSIndexPath indexPath)
    {
        return base.EstimatedHeight(tableView, indexPath);
    }

    public override UITableViewCell GetCell(UITableView tableView, NSIndexPath indexPath)
    {
        throw new NotImplementedException();
    }

    public override nint RowsInSection(UITableView tableview, nint section)
    {
        throw new NotImplementedException();
    }
}