This build was as GM in early October 2019, then pushed to the public. The problem? It had bugs related to:
If you downloaded Catalina specifically during the week of October 7, 2019 using a specific Apple ID: macos catalina 1015 19a583 mac app store dow
Before you download macOS Catalina 10.15.19a583, make sure your Mac meets the system requirements: This build was as GM in early October
Apple stores every single build on content-delivery networks (CDNs). For build 19A583, the file name is specific. macos catalina 1015 19a583 mac app store dow
What is that Mac currently running?