I have no support/technical question and have seen the support category. (Be aware that direct support questions will be deleted.)
on
Tonight after the upgrade to 1.57.1 I had the same issue as after the upgrade to 1.57.
The lines in the file /etc/apache2/sites-enabled/001.nextcloud.conf for letsencrypt:
SSLCertificateFile /etc/letsencrypt/live/xxxx/fullchain.pem
SSLCertificateKeyFile /etc/letsencrypt/live/xxxx/privkey.pem
were overwriten by snakeoil certs.
The same lines in /etc/apache2/sites-enabled/ncp.conf are not changed
This happened on all tree installations that I manage.