If i understand your question correctly then you can try following
- Create Scheduled scan policy first for a group you can name it as Test with Time which you want to be scheduled
- Move machines to this group
- Test the machines if they are scanning at the time scheduled
- And move all the machines to this group Test which can be renamed in Sepm 12.1.
This is a matter of policy only
Alternatively you can assign the scheduled scan policy to this group too
example group 1 has policy already assigned with time specfied where you want the machines to scan and remaining machines are in another group then go to policies av as policy scheduled scan right click and assign this scan policy to the new group
Or
Simply Inherit the new group with first group and it will take the policies which are assigned to group1 which are configured .