macOS Catalina intermittently issuing "Your computer is now running on UPS backup battery power. Save your documents and shut down soon"

Hi mattgroves,

Welcome to Apple Support Communities. I understand you're seeing an unexpected pop-up notification on your Mac. I can help shed some light.

You mentioned updating your Mac to macOS Catalina. There's now a supplemental update available for macOS Catalina. I recommend making sure that your Mac is fully updated to the latest version. This helps provide software improvements and enhanced security updates. If needed, here's how to update the software on your Mac: How to update the software on your Mac

You may also want to try resetting the System Management Controller, as this controls many of the low level power management systems that might communicate with the UPS:

How to reset the System Management Controller (SMC) on your Mac - Apple Support

If you continue to see these notifications after verifying that you are fully updated and reset, you may want to reach out directly to the UPS manufacturer/vendor. Depending on the particular UPS, it may use the built-in monitoring and management options in System Preferences > Energy Saver, or it may have its own installed software. You may want to verify with the manufacturer if the UPS is updated and compatible with Catalina. Also, if the UPS has a USB communication cable, make sure that it is plugged directly into the Mac and not routed thorough a hub or extender.

Cheers!