Well that's good for me to know in case mine stops working. I have it working at 3 sites and that log entry date is accurate so it just worked for me on the 10th. It's interesting, cloudflare still says to use ddclient here, on a page that also talks about using API v4
That sends you to this page which still says to use ddclient
https://www.cloudflare.com/technical-resources/#ddclient
but strangely on the ddclient protocol wiki cloudflare isn't there. I'm pretty sure it was there at one time... The main problem I had setting up cloudflare myself was I was missing the line
options zone=mydomain.com
Failing that, you could always use dnsomatic which works with ddclient (use dyndns2 as your option), and add your cloudflare address in dnsomatic. That's what I did before EdgeOS updated ddclient