I have two groups, that I'm trying to bulk update into another group and use an attribute named 'Position' to distinguish between volunteer roles.  For example the groups are named 'Classroom Buddy' and 'Classroom Aid.' The new group is named 'Classroom Volunteers.'  What I'd like to do is bulk update from 'Classroom Buddy' into 'Classroom Volunteers' and set the attribute position to 'Buddy.'  I then want to repeat that process for the group 'Classroom Aid.'  What I'd like to accomplish; however, is if a person is in both of the two original groups, I'd like them to appear in the new group with both of the positions noted.

Any thoughts on best practices to accomplish this task?