You can check AMD's Tech and Documentation site and see if there are any public docs concerning the Zen 3+ from here: AMD Technical and Documentation
If there aren't any then you can check at a later date and see if it has been added to the site.
This site might have some information in the future also: Data Sheets website
NOTE: if you are a developer that needs the information to create or manufacture a new product using AMD hardware then you probably will need to sign a NDA document to get AMD Non-Public tech documents.