This isn't a Cloudflare-specific issue. Level 3/CenturyLink are in trouble. Affecting other providers (see, for example, Fastly's Status page: https://status.fastly.com/).
"The IP NOC with the assistance of the Operations Engineering team confirmed a routing issue to be preventing BGP sessions from establishing correctly. A configuration adjustment was deployed at a high level, and sessions began to re-establish with stability. As the change propagates through the affected devices, service affecting alarms continue to clear"