telemetry
Look in your scheduled tasks and you'll find it. I haven't dissected the packets to see what it contains but it's a helleva lot of information because it bogged down my quad-core 8GB ram PC running on a 90Mb/s connection for nearly 10 minutes the night I discovered it. I had already opted out of CEIP and disabled the W10 KB's that were known at the time. Doing those things does NOT remove the scheduled task the KBs created when installed. You have to go in and manually remove those.
I bet the telemetry gets sent to a different IP than the updates come from, so I'm considering digging that info out of my firewall logs and putting a permenant block against those IPs.
So shameful M$... I've got enough work to deal with, now I have to do this shit to protect my already rock solid security at home.