Google has upgraded the Search Console reports specifically for the Q&A and FAQ structured data. Now Google will check the validity of FAQ and Q&A structured data that is below the root entity level.
Google said previously the report only flagged entities at the root level, not below the root entity level.
So if you see an increase valid, or warning, or invalid with your FAQ and Q&A items, that would not be such a huge surprise. Google said this is "to reflect an accurate count of root and nested entities that we found on your site."
This change went into affect on March 2, 2021.
Forum discussion at Twitter.
