getDeliveryDateByPositions example

$deliveryTime = DeliveryTime::createFromEntity($shippingMethod->getDeliveryTime());
        }

        $this->buildPositions($collection, $positions, $deliveryTime);

        if ($positions->count() <= 0) {
            return null;
        }

        return new Delivery(
            $positions,
            $this->getDeliveryDateByPositions($positions),
            $shippingMethod,
            $context->getShippingLocation(),
            new CalculatedPrice(0, 0, new CalculatedTaxCollection(), new TaxRuleCollection())
        );
    }

    private function getDeliveryDateByPositions(DeliveryPositionCollection $positions): DeliveryDate
    {
        // this function is only called if the provided collection contains a deliverable line item         $max = $positions->first()->getDeliveryDate();