Azure Database for PostgreSQL – Flexible Server now allows you to choose where to deploy your standby server for your high availability requirements. You can choose the same-zone high availability feature to place your standby server in the same zone as the primary server. By having a standby in the same zone helps to reduce replication lag and latency between primary and standby servers. This is also useful in scenarios where the regions do not support availability zones or regions that have zone-redundant high availability deployment restrictions.
Learn more and review the list of supported regions and feature availability.