[seqizz]

Looks like it is generating on-the-fly. No? Second request for each generation (unique number) takes no time.

  for a in `seq 1000 2000`; do wget "https://bunnynet-avatars.b-cdn.net/.ai/img/dalle-256/avatar/email-${a}/rabbit.jpg?width=128&hiEbunny=is_this_secure_though" ; done

[jchw]

Almost assuredly, it is generating on the fly, then caching.