You are seeing the following errors in the URT:
"ORA-39082: Object type PACKAGE BODY:"UPGRADE5"."UPGRADESCHEMA_PRELOAD_<version>"
15.x/16.x
These are packages used in previous upgrades.
The "UPGRADESCHEMA_PRELOAD" package was used during the upgrade of previous versions (example: 15.5 to 15.8). Since that upgrade is already completed those packages are no longer used. This error can be ignored and should not effect the finally summary report at the bottom of the URT.