CentOS 8 (reliability and features of Red Hat Enterprise Linux 8, but without licensing costs) will be maintained until the end of 2021 and will continue with CentOS 7 which will remain accepted until the end of its life cycle.
In conclusion, at the end of 2021, CentOS 8 will no longer be maintained, and CentOS 7 will remain in accepted maintenance until 2024.
For those who want to use Centos 8 there is Centos Stream. Here's how to switch to Centos Stream:
root@centos-linux# dnf install centos-release-stream
root@centos-linux# dnf distro-sync
root@centos-stream# cat /etc/centos-release
CentOS Stream release 8