The 2024 version of DMTN-065 specifies that labels for Region and Observing Mode should be added to catalogue tables so that data could be queried based upon these labels, specifically for special programs.
Hi Suber, these labels are the anticipated implementation for users to be able to query and subset data products for special programs. The exact names or types of labels may evolve to best serve the science community, but there will be functionality for subsetting data.