HFM Member lists

Hi, we have some C1 movement tables which are used against accounts that do not sit under 1 common parent or there are other accounts under the same parent that use a different C1 movement table. Is there is an easy way to write a member list that effectively uses each of the members in the UD2 field as a new member list without having to define each member list?  I think this would be using a dynamic member list? Is there any guidance on syntax construction at all? Thanks