About 4.5 years back, you posted one time with respect to a similar issue that I assume you were having with your then 'new' C-5 hub. I suggested updating the firmware on your Leviton devices. I never heard back from you. What happened? Did you find a way to update the Leviton Z-Wave firmware?
Just curious if the same issue is re-rearing its ugly head, or if this is something completely different? The Z-Wave radio has gone from a 500 series in the C5 to an 800 series in the C8/C8Pro. Could be something to do with that as well. 