On 9.10.2019 9.01, Aki Tuomi via Dovecot-news wrote:
> We have now buster packages available starting from 2.3.8. You can find
> them from https://repo.dovecot.org/ >
> In related news, we are planning on dropping packages for Debian Jessie,
> Ubuntu 18 and CentOS6 starting from 2.3.9.
> Aki Tuomi
> Open-Xchange oy
And of course we are talking about Ubuntu 14.04, and not Ubuntu 18.