The problem is when you do, instead of their units continuing to power your devices via power from the wall, they shut off power to all their battery ports. So CyberPower battery units can and will cause outages for your devices without you even having a power outage event. It’s a critical design flaw their competitors don’t share.
I’ve never seen a CyberPower not cut power to its battery ports when the battery failed, which I’ve seen dozens of times since the failure rate on them was bordering on the absurd. When contacting CyberPower to warranty them, they told us that was normal and that the units were designed that way.