programatically choose the payment method and skip the step

[krtschmr]

  def select_default_payment
    self.payments_attributes = [{"payment_method_id" => available_payment_methods.select{|x|x.type == "Spree::PaymentMethod::BankTransfer"}.first.id}]
    self.save
  end

this in theory will work, always assign the BankTransfer to the order. Sometimes, which i can't debug, the payment method is getting lost. is there another way to force a certain payment method to an order?