Update Releaseslines are actively developed for 10 months. This means that new versions are released, including new Java versions, CPUs, and PSUs. It also means there is a four month overlap between the creation of a new Update Release line and the end of support for the previous one. You can choose when to upgrade to the new Upgrade Release lineduring the four month window. You can choose to stay on an older Update Release line, but Azul does not make additional releases on those lines as often and does not release CPUs within the 48-hour SLA.