Extend Openshift 4 timeline-based lifecycle from 18 to 24 months

1. Proposed title of this feature request

Extend Openshift 4 timeline-based lifecycle from 18 to 24 months for minor or specific releases, for example for EUS releases.

2. What is the nature and description of the request?

This RFE is for extend up to 24 months timeline-based lifecycle of Openshift 4, minor releases or specific releases, to let customer who can not perform at least one upgrade of the platform per year, have more time to plan/test/validate the Openshift upgrade path , operators and bussinessa applications.

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

Customer can not perform one upgrade of the platform per year because they have a large amount of clusters, environment and locations, so testing applications with new ocp versions, checking k8s api changes, testing new upgrade path, upgrade and check new operator versions, etc takes a lot of time before upgrade on production clusters. Once the all those things are completed, customer has to plan/prepare the upgrade for pre/production clusters during weekends which can take months for all clusters. Considering the Openshift/k8s is in constant change, not performing those tests/validations could affect to the core services which being in the banking sector is very confident on the reliability of the platform. We’re working closely with PMs (Ju Lim), to explain to the customer upgrade strategies, with Services automating the upgrade process, and recently customer has completed an upgrade, even though considering an timeline-based lifecycle extension definetly helps.