Yes you can.
If you specify an existing config directory, the new version of ORDS will connect to the configured databases and check the version of ORDS installed. It will then prompt for the SYS password for each database so it can perform an upgrade of the ORDS objects, without affecting the existing metadata. These upgrades are typically very quick and don't require additional prompts.
If you specified a new config directory you will be prompted for the database connection details, just like a conventional installation, but ORDS will still upgrade any database objects that are already present.
If you are running ORDS under an application server, you will have to redeploy the "ords.war" file before starting the application server.
In order to preserve the old settings for a later use if required, you just have to rename the old Ords folder into something like "ords_old_date" and unzip the new ords folder at that location.