Description:

Please notify customers when ROSA upgrade path gets blocked and when back to unblocked so they can schedule and prepare upgrades accordingly.

Proposed title of this feature request: Notify customers when upgrade paths get blocked

What is the nature and description of the request?:

Why does the customer need this? (List the business requirements here):

Some ROSA upgrade paths (e.g to 4.14.x / 4.15.x etc) have been suddenly blocked and this has been confusing customers. Some of them have prepared and scheduled an upgrade to a certain version but later right before the version upgrade, they found out that the upgrade path is unavailable and it is causing big confusion and inconvenience. If we can't avoid upgrade path blocks but at least we should notify customers timely.

List any affected packages or components:
Related JIRA: https://issues.redhat.com/browse/OHSS-35796?jql=text%20~%20%22rosa%20upgrade%20path%22

Related Slack: https://redhat-internal.slack.com/archives/C021EMWAQ76/p1722241017204869