IBM's service policy is to provide maintenance (service) for each release of z/OS® for five years following their general availability (GA) date. However, service on the last release of a version might be extended beyond the intended five-year period. Before withdrawing service for any version or release of z/OS, IBM® intends to provide at least 12 months notice. For end-of-service (EOS) dates, including those for z/OS V1R12 and z/OS V1R13, see http://www.ibm.com/systems/z/os/zos/support/zos_eos_dates.html.

The service policy for z/OS also applies to any enhancements, such as the z/OS V1R4 enhancements that were provided to support the z990 server.

Program temporary fix (PTF) distributions, including Recommended Service Upgrades (RSUs), will continue to be available monthly while a release is current. Service testing for a release will be performed for five quarters after the general availability date for that release.