Thanks Jon for quick response.
We've been running our Labkey Server on CentOS 7 for the past 6 years and it has worked great. The reason for the upgrade came up with the new versions of Labkey Server that require newer versions of Postgres and Java, that are not supported on CentOS 7. While we could upgrade to CentOS 8 and possibly be happy with that, we are looking for more sustainable (i.e. supported in future) version of Linux.
We run the Labkey server on a Linux cluster along with other proteomics software that may not be happy with Ubuntu/Debian.

Thanks,
Tomas