Hi Icyman,
Since you have installed new FW on your router, the setting of the router MAY NOT be the same as previous. You may need to
1. Reset your printer network configuration - reset printer network configuration
2. Reconnect to the new SSID projected by the FW-updated router again [be it the same SSID] recconnecting to establish the connection.
Below link show some information regarding router reset/reconfiguration impact to printer wireless connection for your reference.
http://www8.hp.com/sg/en/campaigns/wireless-printing-center/reconfiguring-system-help3.html
hope this help...
Although I am HP Employee andI am speaking for myself
>> "Marking" this as RESOLVE, If my post help RESOLVE your issue and help others
>> Click THUMB UP icon if you appreciate the "REPLY"