Low uplink speed: 10kbps

That's not a typo: 10-20 thousand bits per second.  There was trouble reported in our Chicago area today, but Comcast claims it is repaired.  Download speed is fine, >150Mbps, however, upload should be 15Mbps (per plan, and has been in the past).  It is so slow that pages (like this one) load slowly, waiting for responses from the browser.  Xfinity's own speed test simply reports "Error" on the uplink test.  Other tests (for example: Google) show intermittent uplink, settling anywhere from 0-50 kbps.

I've been through the bot loop several times, but the line of questions never arrives at the problem. The bot seems unable to do an uplink speed test.   I've probed the modem (ARRIS DOCSIS 3.0 Cable Modem)​, and all down and up channels are locked and have good signal strength.  

Oddly, Comcast claims there is no longer trouble in my area, yet there is no place that I can find to report trouble., and no way to reach a human.