Update 2021-05-05: The Federal Foreign Office reported on Wednesday (05 May) that returning fully vaccinated residents are subject to a five-day quarantine requirement, with a COVID-19 test conducted on the fourth day of quarantine. Travellers from certain countries are exempt from the quarantine requirement (see here), but must undergo COVID-19 PCR testing on the sixth and twelfth days in the country, the second test is not required for fully vaccinated residents. All other travellers must go into quarantine for ten days and have a COVID-19 test carried out on the eighth day of quarantine.