Can you find out what specifically would cause a Z wave device using an edge driver to be marked off-line?
For Zigbee, it used to be if it had missed three check-in‘s. And later I think it was changed to be if it had been more than one hour since it had checked in.
But since z wave devices don’t have the same kind of check in process, I just wondered what smartthings is using to define these devices as being “off-line.“
(“Offline” itself, of course, is a term that shouldn’t really apply to a Mesh network at all since there isn’t a continuous connection between the devices and the hub. The correct term would be “non-responsive.“ or “unreachable.” But I know “offline” is a term that smartthings has used for several years, so I understand continuing with it, even if it’s going to drive network engineers crazy. 
)