Remote MOVEit Central Admin users should expect to upgrade MOVEit Central Admin each time MOVEit Central is upgraded; the only way to take advantage of new features in MOVEit Central is to configure them with a matching MOVEit Central Admin. In fact, modern versions of MOVEit Central Admin will only work with a particular range of MOVEit Central versions.
There are no special considerations when upgrading an existing MOVEit Central Admin. Almost all of Admin's configuration information (except for its recent host list) is obtained from MOVEit Central after connecting, so upgrades are easy and painless.