Most redistricting discussions focus on the maps, who draws them, what criteria they must meet, and how they will hold up in court. But every redistricting map built from 2030 Census data will ultimately rest on a foundation that GIS and redistricting staff rarely talk about: the Census Bureau's residential address list. The Local Update of Census Addresses operation is the first to occur in every decennial census cycle, and it gives state, tribal, and local governments their only opportunity to directly help ensure an accurate enumeration by reviewing and submitting updates or corrections to the confidential address list before…