My current firmware for my C3700-N600 is Firmware Version V2.02.08

Can anyone tell me if there is an updated newer version for my C3700-N600 modem. If so, can I get instructions on how to upgrade the firmware? Comcast has stepped up their throttling techniques. I have blast up, which is like $90 bucks a month. You are supposed to get 200mbps up and 10 dwn. unfortunately I only get those speeds after I call and complain about slow speeds. I also am running a Linksys WRT1200AC router with the latest DD-WRT firware and a VPN. Lately it seems they're aware that I'm using the router. I thought with my type of equiptment the people at FlashedRouters told me I would have ironclad security -- nearly undetectable by comcast. "If they can't see your traffic, they can't throttle yiour traffic." -Ironclad my nutsack. Please forgive my frustrations. Any information would be greatly appreciated. TY!