Update an existing package using uniqueid. Submit the full intended definition, including report and destination collections. Data-driver changes can trigger SQL validation; the masked existing password is handled specially by this update path. The response echoes the submitted model and is not an independent database read-back. Include both EmailDestinations and DiskDestinations as non-null arrays. Use [] for an unused collection; use JSON when an empty collection is needed. Form examples include both an email destination and a disk destination. Replace the example recipients and paths with your intended destinations. Preserve the complete intended destination lists and their existing DestinationId values. Omitting an existing destination from a list removes it. For a SQL data driver, Password="*****" reuses the stored password for this package; an existing data-driver record must be available or the request fails. The marker is not a new credential. Changing DSN, UserId or Query triggers validation using the retained password. To change the password, supply the new value. This preservation rule applies to this update operation and must not be assumed for creation or unrelated endpoints.