diff --git a/Dockerfile b/Dockerfile
index af50778..1617bf8 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,36 +1,13 @@
-# -----------------------------------------------------------------------------------------------
-# POSTGIS and TimescaleDB (inc. toolkit for hyperfunctions) image built for aarch64 support
-# using timescaledev/timescaledb-ha base image with:
-#
-# - OR specific ENV variables and a healthcheck added
-# - PGDATA path set to match old Alpine image (for ease of DB migration)
-# - POSTGRES user UID and GID changed to match old Alpine image (for ease of DB migration)
-# - OR_DISABLE_REINDEX env variable with associated scripts to determine if a REINDEX of the entire DB should be carried
-#   out at first startup with existing DB (checks whether or not $PGDATA/OR_REINDEX_COUNTER.$OR_REINDEX_COUNTER exists).
-#   This is used when a collation change has occurred (glibc version change, muslc <-> glibc) which can break the indexes;
-#   migration can either be manually handled or auto handled depending on OR_DISABLE_REINDEX env variable value.
-#   NOTE THAT A REINDEX CAN TAKE A LONG TIME DEPENDING ON THE SIZE OF THE DB! And startup will be delayed until completed
-#   This functionality is intended to simplify migration for basic users; advanced users with large DBs should take care of this
-#   themselves.
-#
-#
-#
-# 
-# timescale/timescaledb-ha image is ubuntu based and only currently supports amd64; they are
-# working on ARM64 support in timescaledev/timescaledb-ha see:
-#
-#     https://github.com/timescale/timescaledb-docker-ha/pull/355
-#
-# See this issue for POSTGIS base image aarch64 support discussion:
-# 
-#    https://github.com/postgis/docker-postgis/issues/216
-# -------   ----------------------------------------------------------------------------------------
-
-# TODO: Switch over to timescale/timescaledb-ha once arm64 supported
-# We get POSTGIS and timescale+toolkit from this image
+
+ARG PG_MAJOR_PREVIOUS=14
+ARG PG_MAJOR=15
+
 FROM timescaledev/timescaledb-ha:pg15-multi as trimmed
 MAINTAINER support@openremote.io
 
+ARG PG_MAJOR_PREVIOUS
+ARG PG_MAJOR
+
 USER root
 
 # Give postgres user the same UID and GID as the old alpine postgres image to simplify migration of existing DB
@@ -54,12 +31,22 @@ RUN chmod +x /docker-entrypoint-initdb.d/*
 # Below is mostly copied from https://github.com/timescale/timescaledb-docker-ha/blob/master/Dockerfile (with OR specific entrypoint,
 # workdir and OR env defaults)
 
+# Get multi all image
+FROM timescaledev/timescaledb-ha:pg15-multi-all as trimmed-all
+
+ARG PG_MAJOR_PREVIOUS
+ARG PG_MAJOR
 
 ## Create a smaller Docker image from the builder image
 FROM scratch
 COPY --from=trimmed / /
 
-ARG PG_MAJOR=15
+ARG PG_MAJOR_PREVIOUS
+ARG PG_MAJOR
+
+## Copy previous PG MAJOR version executable
+COPY --from=trimmed-all /usr/lib/postgresql/${PG_MAJOR_PREVIOUS} /usr/lib/postgresql/${PG_MAJOR_PREVIOUS}
+COPY --from=trimmed-all /usr/share/postgresql/${PG_MAJOR_PREVIOUS} /usr/share/postgresql/${PG_MAJOR_PREVIOUS}
 
 # Increment this to indicate that a re-index should be carried out on first startup with existing data; REINDEX can still be overidden
 # with OR_DISABLE_REINDEX=true
@@ -86,9 +73,11 @@ ENV PGROOT=/var/lib/postgresql \
     POSTGRES_DB=${POSTGRES_DB:-openremote} \
     POSTGRES_USER=${POSTGRES_USER:-postgres} \
     POSTGRES_PASSWORD=${POSTGRES_PASSWORD:-postgres} \
+    PG_MAJOR=$PG_MAJOR \
     OR_REINDEX_COUNTER=${OR_REINDEX_COUNTER} \
     OR_DISABLE_REINDEX=${OR_DISABLE_REINDEX:-false} \
-	POSTGRES_MAX_CONNECTIONS=${POSTGRES_MAX_CONNECTIONS:-50}
+    POSTGRES_MAX_CONNECTIONS=${POSTGRES_MAX_CONNECTIONS:-50} \
+    OR_DISABLE_AUTO_UPGRADE=${OR_DISABLE_AUTO_UPGRADE:-false}
 
 WORKDIR /var/lib/postgresql
 EXPOSE 5432 8008 8081
diff --git a/README.md b/README.md
index 447e7e0..2e24570 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,28 @@
 # Postgresql docker image
 [![build multirach postgresql Docker image and push to it dockerhub](https://github.com/openremote/postgresql/actions/workflows/postgresql.yml/badge.svg)](https://github.com/openremote/postgresql/actions/workflows/postgresql.yml)
 
-PostgreSQL docker image based on [Timescale's](https://www.timescale.com/) [timescaledev/timescaledb-ha](https://hub.docker.com/r/timescaledev/timescaledb-ha) docker image which contains post GIS and timescaleDB extensions.
+ POSTGIS and TimescaleDB (inc. toolkit for hyperfunctions) image built for aarch64 support using `timescaledev/timescaledb-ha` base image with:
+
+- OR specific ENV variables and a healthcheck added
+- PGDATA path set to match old Alpine image (for ease of DB migration)
+- POSTGRES user UID and GID changed to match old Alpine image (for ease of DB migration)
+- Auto upgrade of database with PG major version changes from previous PG major version; can be disabled using
+  OR_DISABLE_AUTO_UPGRADE=true.
+- OR_DISABLE_REINDEX env variable with associated scripts to determine if a REINDEX of the entire DB should be carried
+  out at first startup with existing DB (checks whether or not $PGDATA/OR_REINDEX_COUNTER.$OR_REINDEX_COUNTER exists).
+  This is used when a collation change has occurred (glibc version change, muslc <-> glibc) which can break the indexes;
+  migration can either be manually handled or auto handled depending on OR_DISABLE_REINDEX env variable value.
+  NOTE THAT A REINDEX CAN TAKE A LONG TIME DEPENDING ON THE SIZE OF THE DB! And startup will be delayed until completed
+  This functionality is intended to simplify migration for basic users; advanced users with large DBs should take care of this
+  themselves.
+
+`timescale/timescaledb-ha` image is ubuntu based and only currently supports amd64; they are working on ARM64 support in timescaledev/timescaledb-ha see:
+
+https://github.com/timescale/timescaledb-docker-ha/pull/355
+
+See this issue for POSTGIS base image aarch64 support discussion:
+
+https://github.com/postgis/docker-postgis/issues/216
+
+TODO: Switch over to timescale/timescaledb-ha once arm64 supported
+We get POSTGIS and timescale+toolkit from this image
diff --git a/or-entrypoint.sh b/or-entrypoint.sh
index f481b5e..6d152af 100644
--- a/or-entrypoint.sh
+++ b/or-entrypoint.sh
@@ -1,7 +1,8 @@
 #!/usr/bin/env bash
 
 # THIS FILE IS FOR MIGRATION OF EXISTING DB TO TIMESCALEDB IMAGE AS TIMESCALE INIT SCRIPTS AREN'T RUN WHEN DB
-# ALREADY EXISTS; IT ALSO DOES AN AUTOMATIC REINDEX OF THE DB WHEN OR_REINDEX_COUNTER changes TO SIMPLIFY MIGRATIONS
+# ALREADY EXISTS; IT ALSO DOES AN AUTOMATIC REINDEX OF THE DB WHEN OR_REINDEX_COUNTER CHANGES TO SIMPLIFY MIGRATIONS
+# IT ALSO AUTOMATICALLY HANDLES UPGRADING OF DATABASE AND DURING MAJOR VERSION CHANGES
 
 source /docker-entrypoint.sh
 docker_setup_env
@@ -20,6 +21,168 @@ if [ -n "$DATABASE_ALREADY_EXISTS" ]; then
         echo "timescaledb.telemetry_level=off" >> "$PGDATA/postgresql.conf"
     fi
 
+    ########################################################################################
+    # Do upgrade checks - Adapted from https://github.com/pgautoupgrade/docker-pgautoupgrade
+    ########################################################################################
+
+    # Get the version of the PostgreSQL data files
+    DB_VERSION=$PG_MAJOR
+    if [ -s "${PGDATA}/PG_VERSION" ]; then
+      DB_VERSION=$(cat "${PGDATA}/PG_VERSION")
+    fi
+
+    # Try and upgrade if needed
+    if [ "$DB_VERSION" != "$PG_MAJOR" ] && [ "$OR_DISABLE_AUTO_UPGRADE" != "true" ]; then
+
+      echo "----------------------------------------------------------------------"
+      echo "Postgres major version is newer than the existing DB, performing auto upgrade..."
+      echo "----------------------------------------------------------------------"
+
+      if [ ! -d "/usr/lib/postgresql/${DB_VERSION}" ]; then
+        echo "Postgres executable version '$DB_VERSION' is not included in this image so cannot auto upgrade"
+        exit 1
+      fi
+
+      # Check for presence of old/new directories, indicating a failed previous autoupgrade
+      echo "----------------------------------------------------------------------"
+      echo "Checking for left over artifacts from a failed previous autoupgrade..."
+      echo "----------------------------------------------------------------------"
+      OLD="${PGDATA}/old"
+      NEW="${PGDATA}/new"
+      if [ -d "${OLD}" ]; then
+        echo "*****************************************"
+        echo "Left over OLD directory found.  Aborting."
+        echo "*****************************************"
+        exit 10
+      fi
+      if [ -d "${NEW}" ]; then
+        echo "*****************************************"
+        echo "Left over NEW directory found.  Aborting."
+        echo "*****************************************"
+        exit 11
+      fi
+      echo "-------------------------------------------------------------------------------"
+      echo "No artifacts found from a failed previous autoupgrade.  Continuing the process."
+      echo "-------------------------------------------------------------------------------"
+
+      # Don't automatically abort on non-0 exit status, as that messes with these upcoming mv commands
+      set +e
+
+      # Move the PostgreSQL data files into a subdirectory of the mount point
+      echo "---------------------------------------"
+      echo "Creating OLD temporary directory ${OLD}"
+      echo "---------------------------------------"
+      mkdir "${OLD}"
+      if [ ! -d "${OLD}" ]; then
+        echo "*********************************************************************"
+        echo "Creation of temporary directory '${OLD}' failed.  Aborting completely"
+        echo "*********************************************************************"
+        exit 7
+      fi
+      echo "--------------------------------------------"
+      echo "Creating OLD temporary directory is complete"
+      echo "--------------------------------------------"
+
+      echo "-------------------------------------------------------"
+      echo "Moving existing data files into OLD temporary directory"
+      echo "-------------------------------------------------------"
+      mv -v "${PGDATA}"/* "${OLD}"
+      echo "-------------------------------------------------------------------"
+      echo "Moving existing data files into OLD temporary directory is complete"
+      echo "-------------------------------------------------------------------"
+
+      echo "---------------------------------------"
+      echo "Creating NEW temporary directory ${NEW}"
+      echo "---------------------------------------"
+      mkdir "${NEW}"
+      if [ ! -d "${NEW}" ]; then
+        echo "********************************************************************"
+        echo "Creation of temporary directory '${NEW}' failed. Aborting completely"
+        echo "********************************************************************"
+        # With a failure at this point we should be able to move the old data back
+        # to its original location
+        mv -v "${OLD}"/* "${PGDATA}"
+        exit 8
+      fi
+      echo "--------------------------------------------"
+      echo "Creating NEW temporary directory is complete"
+      echo "--------------------------------------------"
+
+      echo "-----------------------------------------------------"
+      echo "Changing permissions of temporary directories to 0700"
+      echo "-----------------------------------------------------"
+      chmod 0700 "${OLD}" "${NEW}"
+      echo "---------------------------------------------------------"
+      echo "Changing permissions of temporary directories is complete"
+      echo "---------------------------------------------------------"
+
+      # Return the error handling back to automatically aborting on non-0 exit status
+      set -e
+
+      # Initialise the new PostgreSQL database directory
+      echo "--------------------------------------------------------------------------------------------------------------------"
+      echo "Initialising new database directory"
+      echo "--------------------------------------------------------------------------------------------------------------------"
+      initdb -D $PGDATA/new
+      echo "------------------------------------"
+      echo "New database directory initialisation complete"
+      echo "------------------------------------"
+
+      # Change into the PostgreSQL database directory, to avoid a pg_upgrade error about write permissions
+      cd "${PGDATA}"
+
+      # Run the pg_upgrade command itself
+      echo "---------------------------------------"
+      echo "Running pg_upgrade command, from $(pwd)"
+      echo "---------------------------------------"
+      pg_upgrade --link -b /usr/lib/postgresql/${DB_VERSION}/bin -B /usr/lib/postgresql/${PG_MAJOR}/bin -d $OLD -D $NEW
+      echo "--------------------------------------"
+      echo "Running pg_upgrade command is complete"
+      echo "--------------------------------------"
+
+      # Move the new database files into place
+      echo "-----------------------------------------------------"
+      echo "Moving the upgraded database files to the active directory"
+      echo "-----------------------------------------------------"
+      mv -v "${NEW}"/* "${PGDATA}"
+      echo "-----------------------------------------"
+      echo "Moving the upgraded database files is complete"
+      echo "-----------------------------------------"
+
+      # Re-use the pg_hba.conf and pg_ident.conf from the old data directory
+      echo "--------------------------------------------------------------"
+      echo "Copying the old pg_hba and pg_ident configuration files across"
+      echo "--------------------------------------------------------------"
+      cp -f "${OLD}/pg_hba.conf" "${OLD}/pg_ident.conf" "${PGDATA}"
+      echo "-------------------------------------------------------------------"
+      echo "Copying the old pg_hba and pg_ident configuration files is complete"
+      echo "-------------------------------------------------------------------"
+
+      # Copy any reindex counter files
+      echo "--------------------------------------------------------------"
+      echo "Copying reindex files across"
+      echo "--------------------------------------------------------------"
+      cp -f ${OLD}/OR_REINDEX_* ${PGDATA}
+      echo "-------------------------------------------------------------------"
+      echo "Copying reindex files is complete"
+      echo "-------------------------------------------------------------------"
+
+      # Remove the left over database files
+      echo "---------------------------------"
+      echo "Removing left over database files"
+      echo "---------------------------------"
+      set +e
+      rm -rf "${OLD}" "${NEW}" delete_old_cluster.sh
+      set -e
+      echo "---------------------------------------------"
+      echo "Removing left over database files is complete"
+      echo "---------------------------------------------"
+
+      echo "**********************************************************"
+      echo "Automatic upgrade process finished with no errors reported"
+      echo "**********************************************************"
+    fi
+
     # Do re-indexing check
     if [ "$OR_DISABLE_REINDEX" == 'true' ] || [ -z "$OR_REINDEX_COUNTER" ]; then
         echo "REINDEX check is disabled"