Finding Paragraphs starting with lowercase

While importing a .txt file I’m finding many broken paragraphs, leading to paragraphs starting with a lowercase. How can I use regex to select the paragraph breaks before said lowercase letters?

I don’t think you can do exactly that because text search doesn’t span paragraph breaks.
But you can do what the subject version of your question asks for: find paragraphs which start with a lower-case letter.
Search for RegEx (?-i)^[a-z]

Thanks so much!