If you do not intend to rebuild your production environment, you may prefer to create your test databases with the for load option of the create database command. This makes your test databases more representative of the current production environment in terms of fragmentation and density.
Create the database using the for load option of the create database command.
Load the backups you made from the production database.
Issue the online database command which automatically upgrades the database if it is not at version 15.0.
For command syntax, see the Reference Manual: Commands.