Hook to display additional shipping info on cart and checkout pages

I have 3 different flat rate shipping methods on my site and I would like to display a sentence providing some extra info by the delivery options on my cart and checkout pages.

I have found this hook ‘woocommerce_before_shipping_calculator’ which displays the notice just below my shipping options on the cart page but it doesn’t display on the checkout page.

What would the correct hook be on the checkout page?