This issue has been resolved and single-file cache purge has returned to normal.
Posted 11 days ago. Nov 07, 2017 - 12:46 UTC
Cloudflare is experiencing delays of up to 2 minutes processing single-file cache purges via the API. The "Always online" feature is also affected. We are actively working to eliminate these delays. In the meantime, you may use the "Purge All" feature, but note that this may cause a surge in traffic to your origin site.
Posted 11 days ago. Nov 07, 2017 - 11:37 UTC
This incident affected: Cloudflare customer dashboard and APIs (Cloudflare APIs).