I've asked an employee to check the CMTS for real-time and historical RF signal reports from your modem. They can also check your local node/plant for any degradation or error reports. You can expect a reply in this thread.
Hey Chunlock. That nighthawk router and the Docsis 3.1 modem is the best money can buy! Are you seeing the same T3 timeouts and upload issues when you bypass the router?
I heard from a coworker (M that you're working with her on Twitter (we sit beside each other). You're in good hands. I'll let her finish with you there.