I don’t like the idea of these updates (major updates) causing issues. Here is an option, as suggested by ZDNet, to recover files in the event you encounter this issue.
For some unknown reason, moving up to Windows 10 version 1809 may delete all the files in user folders. The folders remain, but the files within them are gone, leaving users in potentially a worse pickle than ransomware victims experience. However, there is a chance that early Windows 10 upgraders who encountered this problem might be able to recover lost files by using the free version of Avast-owned Recuva recovery software.