Hey, I get the same, 6pm m-f things get choppy for awhile. I was thinking it was just the neighborhood coming online, but I live in a rural sb area, so the chances for that may be slim. I have a year old panama, 300/30 unlimited plan. Using wired. I've also noticed a slight increase in latency all the time via my office vpn.
Have not done any investigating yet, other than speedtest, which didn't show anything unusual.
The main thing I want to improve is latency on my work vpn. I think I will be testing a few different modem/routers to see if I can get any improvement. No gigablast option in my neighborhood yet, but I'll still only try newer docsis 3.1 modem/routers.
I don't think a change in modem router will fix the 6pm issue. But if I see any improvement I'll report back.
Good luck