Am I correct that there is a rather severe bug in the DHCP server in the Hub 3 where
(1) leases are renewed daily irrespective of the lease length set in the options, and
(2) instead of extending existing leases every device is disconnected from the network and must re-connect.
The answer to this appears to be yes. I found this out myself, so no customer help from you so far.
See if you can do better with this:
Is this bug fixed in Hub 4 or 5?