Network creators admit[1] that the architecture of CoralCDN isn't very well suited for supporting content availability (as opposed to helping with handling load & bandwidth usage).
For example, at any point in time, content can be removed from cache—before completing its usual 24h lifecycle—to accommodate resource usage for different sites.
[1] "Experiences with CoralCDN: A Five-Year Operational View" http://www.coralcdn.org/docs/coral-nsdi10.pdf