So in order to get the new speeds you need to reboot your modem?
Yes; the change is done via modem configuration files which are fetched by the modem from Comcast only when the modem reboots and if the config file has changed since the last reboot. So if you reboot and you don't see a change in speed then the upgrade hasn't been rolled out to your area. -- Making life hard for others since 1977. I speak for myself and not my employer/affiliates of my employer.