Forego BBB (they are not in any position to help). Instead file a complaint with FCC. Keep track of your down time as well. Cox is able to credit your account at around $8 per day of services being down.
Good luck. My services have been problematic for almost 4 weeks now. Some days I have zero internet.
I'm in the same boat now. They sent me the email about upgrading to DOCSIS 3.1 and checking into their other plans. I did that, and checked out Gigablast which is actually $3 a month cheaper than the plan I was on. It was blistering fast for a couple days and now for the last 5 days, just constant drops. Getting 800-850 down and like 0-5 upstream, maybe... I show 40-60% packet loss.
I ran diagnostics on my equipment, they are perfect, right in the sweetspot with Power, SNR on the up and down channels. Plus I know it worked great for a couple days, was getting like 850/35 constantly.
They have been telling me there is "noise" on the line and techs are working on it, but then I check their website and they say everything is fixed. Now it's starting to effect my job since I'm working from home.
Getting ridiculous! They have credited me for 5 days last week so far though. At this rate though, I might get my (non) internet for free this month. Been a customer for 22+ years.
I can attest to a similar experience. One consideration is how your property is tied into your service area. For example, my fiber connection was the only one in my neighborhood and tied in to the terminal that supported everyone else who was still on coax. When that terminal has issues such as interference or what Cox likes to call “egress” my fiber line dropped completely. After some hunting around, we found a terminal in the ground with no connections on it and moved my fiber line to it. I’m now experiencing the performance expected with fiber (300 down/200 up on average via WiFi).
It was a 5 week long saga but I think we figured it out for now. As an added bonus, the terminal we found is on my land. Not saying it’s mine alone but not a likely choice for use given its location.