The first thing I recommend is checking to make sure you have the latest moveclient.vbs script. This should be in the SEP 12.1 RU2 download under the nosupport directory.
You can set the name of your Temp group in the following line. By default it uses the SEPM default Group Name as seen below.
Dim TempGroupName : TempGroupName = "Default Group"
The next setting determines if the moveclient.vbs script will process clients from all groups or just from the defined TempGroupName
Dim OnlyCheckClientsInTempGroup : OnlyCheckClientsInTempGroup = False
You can't use this to move SEPM group named GroupA to SEPM group named GroupB but you could get creative and use the options available in the script such as IPGroups to move all clients in GroupA to GroupB.
IPgroups.txt
This file contains a list of IP addresses (IP ranges or IP addresses with subnet notation) and
group names separated by a comma. The script will search for clients with the IP address listed
and move them to the associated group. This supports single IP addresses, IP ranges and IP
subnet notations.
Format:
IP,GroupName
IP,GroupName,DomainName
IP,GroupName,DomainName,Description
Sample text file:
172.24.20.171,Marketing
10.0.0.4,Group1
192.168.0.1-192.168.0.254,Group1\subgroup1
192.168.0.1/24,Group1\subgroup1
172.16.0.2,Group2\subgroup1
207.33.111.27,Group3
Please always test before making production changes. I cannot recommend changes in your production environment.