shipping-notifications/ShippingNotifications/view/frontend/templates/shipping_notification.phtml

<?php
    $shipping_category = $block->getShippingCategory();
    $delayedCategs = $block->getDelayedShippingCategories();  
    $finalBlock = $this->getLayout()->createBlock('Magento\Cms\Block\Block')->setBlockId($block->getBlock());

    if($delayedCategs){
        foreach($delayedCategs as $categ){
            if($shipping_category == $categ){
                if($finalBlock){
                    echo $finalBlock->toHtml();
                }
                break;
            }
        }
    }