I attempted an NS move to CF last Friday and it failed. My DNS records were going up and down for a few hours until I switched back to my previous DNS host. Despite this, my CF dashboard is showing me daily statistics for the domain. How could it know this information if CF is not my DNS host?
What feature, service or problem is this related to?
Without the domain it’s hard to know, but likely requests for your domain were hitting the Cloudflare edge. Maybe your domain went active for a short period or bots saw the Cloudflare nameservers in place or were used and just hit any Cloudflare proxy IP addresses for it.