22.04 LTS is available in stable images stream prior to its official release

[Vladimir Grevtsev]

$ curl -s https://images.maas.io/ephemeral-v3/stable/streams/v1/com.ubuntu.maas:stable:v3:download.json | egrep "22\.04" | head
  "com.ubuntu.maas.stable:v3:boot:22.04:amd64:ga-22.04": {
   "release_title": "22.04 LTS",
   "subarch": "ga-22.04",
   "subarches": "generic,hwe-p,hwe-q,hwe-r,hwe-s,hwe-t,hwe-u,hwe-v,hwe-w,ga-16.04,ga-16.10,ga-17.04,ga-17.10,ga-18.04,ga-18.10,ga-19.04,ga-19.10,ga-20.04,ga-20.10,ga-21.04,ga-21.10,ga-22.04",

But it looks like it should be in "candidate", not "stable" stream.

[Vladimir Grevtsev (vlgrevtsev)]

Adding ~field-high since this is causing confusion to existing customers who are running MAAS.