Update:
Some WOW! Internet customers are reporting to us that the issue has been resolved for them. They appear to have in common to previously have been routed through Atlanta, GA and are probably now routed through a new peering connection between WOW! and Cloudflare in Ashburn, VA, which was set up yesterday morning.
Other WOW! customers have reported to us that the issue persists and have sent us detailed clients logs (per instructions above). They appear to have in common to be routed through Chicago, IL. The investigation continues.