This is little bit strange.
But can we create GDG with VSAM model data set and it generations instead of using tht ordinary sequential files, because both the GDG and VSAM files using the same utility (IDCAMS)?
Specifies that a generation data group (GDG) entry is to be defined. A GDG can contain both SMS- and non-SMS-managed generation data sets. A generation data set (GDS) cannot be a VSAM data set.