The default channel of 4.15, 4.16 clusters is stable-4.14.
    

4.16.0-0.nightly-2024-01-03-193825
    

Always
    

    1. Install a 4.16 cluster
    2. Check default channel
# oc adm upgrade 
warning: Cannot display available updates:
  Reason: VersionNotFound
  Message: Unable to retrieve available updates: currently reconciling cluster version 4.16.0-0.nightly-2024-01-03-193825 not found in the "stable-4.14" channel

Cluster version is 4.16.0-0.nightly-2024-01-03-193825

Upgradeable=False

  Reason: MissingUpgradeableAnnotation
  Message: Cluster operator cloud-credential should not be upgraded between minor versions: Upgradeable annotation cloudcredential.openshift.io/upgradeable-to on cloudcredential.operator.openshift.io/cluster object needs updating before upgrade. See Manually Creating IAM documentation for instructions on preparing a cluster for upgrade.

Upstream is unset, so the cluster will use an appropriate default.
Channel: stable-4.14

    3.
    

Default channel is stable-4.14 in a 4.16 cluster
    

Default channel should be stable-4.16 in a 4.16 cluster
    

4.15 cluster has the issue as well.