Systems do not always arrive at the current OpenBoot™ architecture and FCode (for server I/O boards) level. In order to maintain consistency, be sure to check their levels and make certain that they are consistent with other systems of the like type and function before moving the systems into production.
If an upgrade is necessary, it is usually done via patches. There will be directions that will explain the process to follow. As usual, when adding patches, test before upgrading.