Hi Oisin,
Thanks for writing in! Most possible cause could be caching. First of all, could you please make sure to clear full cache and re-test your issue again by following this guide (https://www.wpbeginner.com/beginners-guide/how-to-clear-your-cache-in-wordpress/).
If you’re still having issues, then switch to the Skeleton mode on your Cornerstone
And if you see those sections, try removing them inside Skeleton mode, save the changes and re-test.
Further I would suggest you to disable your 3rd party plugins to see if you’re experiencing a plugin conflict. If the issue is resolved, then you can activate your plugins one by one to see which plugin causing the issue.
In case if you cannot isolate the issue, provide us with your WordPress login credentials in a secure note to check your issue further.
Thanks!