Well, not sure what the difference is. A battery level is a battery level 
Problem with the âcard errorâ is, it is a sending device, not a receiving one. So an empty battery or lost connection doesnât âerrorâ a card, Homey doesnât know if itâs offline, and the last known value is just the actual value.
With f.i. zigbee sensors itâs a similar situation. When they lose connection (but not actually left network) to Homey, itâs nothing more then a sensor which doesnât update anymore, and ânothingâs wrongâ.
For those âsilencedâ devices, I have a flow which checks the last reported status every x hrs
