little-snitch-rules/rules/iCloudPrivateRelay.lsrules

{
  "description" : "",
  "name" : "iCloud Private Relay",
  "rules" : [
    {
      "action" : "deny",
      "ports" : "80",
      "process" : "\/usr\/libexec\/networkserviceproxy",
      "protocol" : "tcp",
      "remote-hosts" : "netcts.cdn-apple.com"
    },
    {
      "action" : "deny",
      "ports" : "443",
      "process" : "\/usr\/libexec\/networkserviceproxy",
      "protocol" : "tcp",
      "remote-hosts" : "mask-api.icloud.com"
    },
    {
      "action" : "deny",
      "ports" : "443",
      "process" : "\/usr\/libexec\/networkserviceproxy",
      "protocol" : "tcp",
      "remote-hosts" : "mask-h2.icloud.com"
    },
    {
      "action" : "deny",
      "ports" : "443",
      "process" : "\/usr\/libexec\/networkserviceproxy",
      "protocol" : "udp",
      "remote-hosts" : "mask-canary.icloud.com"
    }
  ]
}