When you need to upgrade PostgreSQL, there are a variety of approaches that you can use. To avoid application downtime, then not all of the options to upgrade postgres are suitable. When avoiding downtime is essential, then you might consider using replication as a means of upgrade, and depending on your scenario, you can choose [&]

https://www.percona.com/blog/2019/04/04/replication-between-postgresql-versions-using-logical-replication/