In the documentation it is mentioned several times that:
We do not recommend CentOS 8 anymore.
However I cannot find a reason anywhere as to why it is not recommended.
Independent of Mailcow there is an EOL end of 2021 for CentOS 8. Redhat decided that there are no following releases of CentOS. In the future there will be rolling releases with CentOS Stream
AllgaeuerBraunvie Seems a bit strange to explicitly mention it as not recommended if that is the reason. There are always releases going EOL, it should not really a concern of mailcow if you decide to use a EOL OS.
I explicitly said - this is independent to mailcow. So I don’t know about the reasons why this was announced by mailcow - anyway “not recommended” != “not allowed”