I've been disconnecting every two hours since I've had FiOS installed. I've pinpointed the problem to the router not renewing it's DHCP lease properly. It helps to reboot the router but that solution doesn't last very long, it begins renewing properly again but after about 8-12 hours it doesn't renew until the lease expires. Obviously there's no manual fix available, no new firmwares and not much a user can do. I've also done a hard reset, force upgrade of firmware, restore to manufactor.