Replace the whole watchlist with these entries, e.g. to sync it from an ERP every night: entries missing from items are removed, entries that stay keep their date. UIDs are accepted as CHE-123.456.789, CHE123456789 or with MWST/TVA/IVA; the check digit must match. Each entry may carry your reference (e.g. a customer number) and a group (e.g. the client a debtor belongs to). All or nothing: one invalid UID rejects the call with every problem listed. New entries get an initial check of the history in the gazette.