upgrade CMDBuild 2.5.0 -> 3.3 (RHEL8)

Should it be possible to upgrade from 2.5.0 to 3.3?

I have created dump from old 32 bit RHEL6 CMDBuild 2.5.0 cmdb_250 database and restored it to fresh RHEL8 CMDBuild 3.3 cmdb_33 database using pg_dump and pg_restore like this:
$ /usr/pgsql-9.4/bin/pg_dump -U tomcat -Fc cmdb_250 > cmdb_250.dump
$ /usr/pgsql-10/bin/pg_restore -U tomcat -d cmdb_33 cmdb_250.dump > 33.log 2> 33_err.log

When I try to configure CMDBuild using web UI the “Test database connection” to new cmdb_33 is ok, but after clicking Configure I get the following error:
“error processing event handlers for event = INSTANCE, subscriber = public void org.cmdbuild.dao.config.inner.DatabaseStatusServiceImpl$1.handleDatasourceConfiguredEvent(org.cmdbuild.dao.DatasourceConfiguredEvent): java.lang.NullPointerException”

CMDBuild creates a new file called database.conf and it seems to be ok.
However when restarting tomcat, the following error comes into cmdbuild-3.3.log:
2020-11-06T20:53:15.897+02:00 [sys:boot] INFO o.c.d.d.ConfigurableDataSourceImpl - postgres driver = org.postgresql.Driver
2020-11-06T20:53:15.898+02:00 [sys:boot] INFO o.c.d.d.ConfigurableDataSourceImpl - postgres driver version = PostgreSQL JDBC Driver 42.2.5
2020-11-06T20:53:15.898+02:00 [sys:boot] INFO o.c.d.d.ConfigurableDataSourceImpl - configure datasource with url = jdbc:postgresql://localhost:5432/cmdb_33 with user = tomcat
2020-11-06T20:53:16.224+02:00 [system] INFO org.reflections.Reflections - Reflections took 21 ms to scan 1 urls, producing 10 keys and 235 values
2020-11-06T20:53:16.980+02:00 [sys:boot] INFO o.c.d.d.ConfigurableDataSourceImpl - postgres server version = 10.0.14
2020-11-06T20:53:16.981+02:00 [sys:boot] WARN o.c.d.d.ConfigurableDataSourceImpl - using unsupported postgres version = 100014 (recommended version is 9.5.x to 10.6.x)
2020-11-06T20:53:17.078+02:00 [sys:boot] ERROR o.c.d.d.ConfigurableDataSourceImpl - error processing event handlers for event = INSTANCE, subscriber = public void org.cmdbuild.dao.config.inner.DatabaseStatusSer
java.lang.NullPointerException: null
at com.google.common.base.Preconditions.checkNotNull(Preconditions.java:787) ~[guava-23.0.jar:na]
at org.cmdbuild.dao.config.inner.PatchImpl$PatchBuilder.withDescription(PatchImpl.java:188) ~[cmdbuild-dao-config-3.3.jar:na]
at org.cmdbuild.dao.config.inner.PatchCardRepositoryImpl.lambda$findAll$0(PatchCardRepositoryImpl.java:47) ~[cmdbuild-dao-config-3.3.jar:na]

Chapter 4 in Techical manual (page 21) won’t help in this.