From the installation guide, page 38 (for 10.1):
Procedure
The following procedure describes how to install the Administration Client on to an administrator’s machine.
To install the Administration Client, perform the following steps:
1.Log on to the machine as a member of the local administrators group.
2.Uninstall any previous versions of the SAP Business Planning and Consolidation Administration Client.
Use Add/Remove Programs in the Windows Control Panel.
3.Point your browser to the Business Planning and Consolidation Web client at <PC_server:port>/sap/bpc/web.
4.Select the Download Center link or icon from the Business Planning and Consolidation Launch page.
5.Select Business Planning and Consolidation Administration.
6.Wait while the installation wizard verifies your prerequisites, then select Next.
7.From the installation wizard, select Next.
8.Select I accept the terms of the license agreement and click Next.
9.Select Next to install the program to the default location.
10.Choose Finish.
I'm assuming once you upgrade your main Server package for the application servers, it would refresh what's available via the download center link.