Meldingen: Apple to reduce accepted TLS certificate term to 398 days
Apple announced at the CA/Browser Forum in February that it will limit the maximum TLS/SSL certificate lifecycle to 398 days as of September 1, 2020.
Certificates issued on or after that date with a term length longer than 398 days will be distrusted in Apple products. Certificates issued before that date are not affected and do not need to be replaced or modified. You can still issue 2-year certificates until August 31, 2020; these remain valid until their their expiration date.