
Apple today appears to have seeded the first beta of an upcoming macOS Catalina 10.15.6 update to developers for testing purposes, one week after releasing macOS Catalina 10.15.5 with battery health management features for Macs.

The macOS Catalina 10.15.6 beta can be downloaded from the Software Update mechanism in System Preferences, as it does not yet appear to be showing up in the Apple Developer Center.
There's no word yet on what features or improvements the sixth update to macOS Catalina will introduce, but it likely focuses on performance improvements, security updates, and fixes for bugs that weren't able to be addressed in the prior update.
Article Link: Apple Seeds First Beta of Upcoming macOS Catalina 10.15.6 Update to Developers