You'll see a few changes in the pipeline. One, as noted, was that now we offer static IPs, with a single IP static being free for residential users on Fusion.
The other is a shift to a new DHCP architecture, and a move away from short leases. The short lease was important in our older infrastructure, as the secured-ARP in the Redback SMS didn't work unless it participated in the lease - so a reboot meant an average of 1/2 the lease time until all customers came back online. Short lease, short downtime.
The Adtran platform doesn't have this limitation, it remembers IP security across reboots, so we'll be extending the lease time a lot in the new deployment.
THAT said, your firewall IS broken if it won't allow a renewal.
With a longer lease interval, it'll just mean a brief downtime every 12 hours or something, but it'll still cause you an outage.
-Dane