Re-printing from email here:

I am running v2.10.0-beta.2 now and noticed that when ech is enabled I got HTTPS DNS (for ECH) records on any and all domain names served by Caddy. I use Cloudflare free plan both for DNS and full cf proxy so my CNAMEs lead to a record which is being changed at most once a day upon intentional IPv4 change.

I am still running beta.2 but have commented new ECH line, deleted the automatically created HTTPS DNS records and everything works fine.