In addition to the double opt-in form, CRM synchronisation and Web shop synchronisation, are there other ways of importing recipients by CSV- or Excel file? If so, are the recipients overwritten?
Recipients can be imported to your address book at any time, by any means (import, synchronisation, web form, API, manually). It is standard procedure that recipient data is updated whenever you import data.
Bounces and unsubscriptions remain intact and are not overwritten.