Question about postgresql version

I had just upgraded my main UCS server to 5.0-0 errata127 and noticed the following error on the server upgrade related to postgres:

Processing triggers for postgresql-common (200+deb10u4) …
Redundant argument in sprintf at /usr/share/perl5/Debconf/Element/Noninteractive/ line 54, line 6.
Obsolete major version 9.6

The PostgreSQL version 9.6 is obsolete, but the server or client packages
are still installed. Please install the latest packages (postgresql-11 and
postgresql-client-11) and upgrade the existing clusters with
pg_upgradecluster (see manpage).

Please be aware that the installation of postgresql-11 will automatically
create a default cluster 11/main. If you want to upgrade the 9.6/main
cluster, you need to remove the already existing 11 cluster (pg_dropcluster
–stop 11 main, see manpage for details).

The old server and client packages are no longer supported. After the
existing clusters are upgraded, the postgresql-9.6 and postgresql-client-9.6
packages should be removed.

Please see /usr/share/doc/postgresql-common/README.Debian.gz for details.

Building PostgreSQL dictionaries from installed myspell/hunspell packages…
Removing obsolete dictionary files:

The update has been finished successfully at Sat 16 Oct 2021 09:37:48 PM EDT.

What version of postgres should be running on this version of Univention - 9.6 or 11?? If 11 how do I fix this issue to get it up to the correct version? Any help on this would be greatly appreciated.