Open Retail > Retail Menu (the locations list) and click Update Stock with AI at the top. This launch is not tied to one location, so the modal shows a Fulfillment date field (used for the template and for any row whose fulfillment_date is blank) and the subtitle Upload a CSV to set stock across every location at once. Each row must carry its own location_id (rows without one are blocked with Missing location_id and no default location for this page). Rows may also mix dates. Everything else - review, fee, receipt, history and undo - works the same; in the history the run is listed with location All Locations.