This is a new issue for me. I have created a post that is longer than the excerpt length set in Customizer. What is happening is the except is being taken from the end of the text instead of the beginning and no “Read More” is presented. All other posts created earlier are working fine. I will send credentials. The blog page is http://www.christenesandesonart.ca/blog/
Shortcodes and tags like <br> could be part pf excerpt, as you know this posts has many <br> tags in the first paragraph. Since <br> tag couldn’t be read, then excerpt will displays next text element. You can add manual excerpt for posts like this. Please add manual excerpt under cornerstone settings tab/general.