Search notes:

$ORACLE_HOME/rdbms/admin/autoupgrade.jar

autoupgrade.jar is the Autoupgrade utility.
The Autoupgrade utility is included with each release update (RU) and the most recent version can be downloaded from My Oracle Support Document 2485457.1.

TODO

java -jar autoupgrade.jar -config ORA21.cfg -mode deploy
Is database ready for upgrade:
java -jar autoupgrade.jar -config PDB1.cfg -mode analyze

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