fail to run postgresql16 after update from postgresql13

Hi

i hope i've got the correct mailing list for this question/problem.  I'm a
novice.

A little history.
I use opensuse tumbleweed and the Kmail/Kontact PIM software which is
contrlled by software called Akondai and this requires a DB.  The default was
Mysql but it caused a lot of reliability issues for me so i migrated to
Postgresql 9.6 (yes, it was a few years ago)

I've since then update the DB to 10, 11, 12 until ver 13 which i
have been using until now.  I  did try updating to ver 14 but it failed with
locale issues during the update and i couldn't get a resolution.

I just recently managed to get the database converted from postgresql13 to
postgresql16 and the data was transferred to the new DB with no issues.

I can't get Akonadi to load as it fails to start postgresql16, its failing
with a message saying it needs postgesql9.6 as the DB was originally created
using 9.6. I can't see why it insists on ver 9.6 being there as i've updated
to ver 16 and that process means i create an empty DB.  I can't even install
Ver 9.6 to see if that cures the problem as its no longer in the opensuse
repos.

Thanks for any help.

-------------- the section below list processes and the errors ----------

I update the DB manually via scripts with one file per action.
1. Backup
# stop akonadi
akonadictl stop
# copy
cp -R $HOME/.local/share/akonadi/db_data $HOME/.local/share/akonadi/db_data_13
# rename
mv $HOME/.local/share/akonadi/db_data $HOME/.local/share/akonadi/db_data_old

2. Create new DB
/usr/lib/postgresql16/bin/initdb --pgdata=$HOME/.local/share/akonadi/db_data
--lc-collate=en_US.UTF-8 --locale=en_US.UTF-8

3. Check upgrade
/usr/lib/postgresql16/bin/pg_upgrade -b /usr/lib/postgresql13/bin -B /usr/lib/
postgresql16/bin  -d $HOME/.local/share/akonadi/db_data_13 -D $HOME/.local/
share/akonadi/db_data  --check

4. Do the upgrade if "3" worked okay
/usr/lib/postgresql16/bin/pg_upgrade -b /usr/lib/postgresql13/bin -B /usr/lib/
postgresql16/bin -d $HOME/.local/share/akonadi/db_data_13 -D $HOME/.local/
share/akonadi/db_data

-----
Here are the error messages from akonadi and the journal.

--------------
~:> akonadictl start
org.kde.pim.akonadictl: Starting Akonadi Server...
org.kde.pim.akonadictl:    done.
~> Connecting to deprecated signal
QDBusConnectionInterface::serviceOwnerChanged(QString,QString,QString)
org.kde.pim.akonadiserver: Starting up the Akonadi Server...
(QFileInfo(/usr/lib/postgresql/bin), QFileInfo(/usr/lib/postgresql/lib64))
QSqlDatabase: QPSQL driver not loaded
QSqlDatabase: available drivers: QSQLITE QMARIADB QMYSQL QMYSQL3
org.kde.pim.akonadiserver: Invalid database object during database server
startup
QProcess: Destroyed while process ("/usr/bin/pg_ctl") is still running.
org.kde.pim.akonadiserver: Shutting down AkonadiServer...
org.kde.pim.akonadicontrol: Application '/usr/bin/akonadiserver' exited
normally...

---------

This is from "systemctl status postgresql.service"

× postgresql.service - PostgreSQL database server
     Loaded: loaded (/usr/lib/systemd/system/postgresql.service; enabled;
preset: disabled)
     Active: failed (Result: exit-code) since Tue 2023-10-31 16:24:13 GMT;
1min 31s ago
    Process: 5916 ExecStart=/usr/share/postgresql/postgresql-script start
(code=exited, status=1/FAILURE)
        CPU: 8ms

Oct 31 16:24:13 Lian-Li systemd[1]: Starting PostgreSQL database server...
Oct 31 16:24:13 Lian-Li postgresql-script[5916]:  Your database files were
created by PostgreSQL version 9.6.
Oct 31 16:24:13 Lian-Li postgresql-script[5916]:  Could not find executables
for this version.
Oct 31 16:24:13 Lian-Li postgresql-script[5916]:  Please install the
PostgreSQL server package for version 9.6.
Oct 31 16:24:13 Lian-Li systemd[1]: postgresql.service: Control process
exited, code=exited, status=1/FAILURE
Oct 31 16:24:13 Lian-Li systemd[1]: postgresql.service: Failed with result
'exit-code'.
Oct 31 16:24:13 Lian-Li systemd[1]: Failed to start PostgreSQL database
server.

----------
From the journal using "journalctl -xeu postgresql.service"

Oct 31 16:24:13 Lian-Li systemd[1]: Starting PostgreSQL database server...
Subject: A start job for unit postgresql.service has begun execution
Defined-By: systemd
Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel

A start job for unit postgresql.service has begun execution.

The job identifier is 2241.
Oct 31 16:24:13 Lian-Li postgresql-script[5916]:  Your database files were
created by PostgreSQL version 9.6.
Oct 31 16:24:13 Lian-Li postgresql-script[5916]:  Could not find executables
for this version.
Oct 31 16:24:13 Lian-Li postgresql-script[5916]:  Please install the
PostgreSQL server package for version 9.6.
Oct 31 16:24:13 Lian-Li systemd[1]: postgresql.service: Control process
exited, code=exited, status=1/FAILURE
Subject: Unit process exited
Defined-By: systemd
Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel

An ExecStart= process belonging to unit postgresql.service has exited.

The process' exit code is 'exited' and its exit status is 1.
Oct 31 16:24:13 Lian-Li systemd[1]: postgresql.service: Failed with result
'exit-code'.
Subject: Unit failed
Defined-By: systemd
Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel

The unit postgresql.service has entered the 'failed' state with result 'exit-
code'.
Oct 31 16:24:13 Lian-Li systemd[1]: Failed to start PostgreSQL database
server.
Subject: A start job for unit postgresql.service has failed
Defined-By: systemd
Support: https://lists.freedesktop.org/mailman/listinfo/systemd-devel
A start job for unit postgresql.service has finished with a failure.

-----------------------

opensuse:tumbleweed:20231030
Qt: 5.15.11 KDE Frameworks: 5.111.0 - KDE Plasma:  5.27.9 - kwin 5.27.9
kmail2 5.24.2 (23.08.2) - akonadiserver 5.24.2 (23.08.2) - Kernel:  6.5.9-1-
default  - kernel-firmware-radeon  20231019