This is a little weird for me:

Using Cloudflare's 1.1.1.1:

  ~> curl -s --doh-url https://cloudflare-dns.com/dns-query https://mensura.cdn-apple.com/api/v1/gm/config | jq -r .test_endpoint
  sgsin3-edge-bx-008.aaplimg.com
  PING sgsin3-edge-bx-008.b.aaplimg.com (17.253.61.15) 56(84) bytes of data.
  64 bytes from sgsin3-edge-bx-008.b.aaplimg.com (17.253.61.15): icmp_seq=1 ttl=52 time=74.2 ms

If I use 8.8.8.8:

  ~> curl -s --doh-url https://dns.google/dns-query https://mensura.cdn-apple.com/api/v1/gm/config | jq -r .test_endpoint
  hkhkg1-edge-bx-007.aaplimg.com
  ~> ping hkhkg1-edge-bx-007.aaplimg.com
  PING hkhkg1-edge-bx-007.aaplimg.com (17.253.85.13) 56(84) bytes of data.
  64 bytes from hkhkg1-edge-bx-007.aaplimg.com (17.253.85.13): icmp_seq=1 ttl=54 time=107 ms

Seems like I'm two different PoPs depending on which DNS I'm using.