Is my firmware too old? - G34

The Cable Operators (MSOs) have complete control of what cable modem/gateway hardware they will allow installed and the firmware it uses, this is because they own the coaxial cable that is connected to the ARRIS G34, because of that the Firmware updates are pushed by them, and any update needed as well. Any associated firmware updates are automatically deployed by the cable operator. This is not an ARRIS only implementation, but the required implementation of any cable device manufacturer.

Even for the device owned by the customers only ISP can send updates to the modem since they are the one activating device and sending signals to the device to provide internet. There is no manual option to update firmware.