Resolution:
The reason for incorporating this feature was that it will not limit our choices of number of schemas. We can configure as many schemas as we want.

The new feature will take the default username/password for schemas other than APPS i.e. for AP schema it will take AP as password.
If the password is other than AP it will throw an error stating wrong username/password. Then we need to provide the changed password and after that it will go through fine.

This feature will not affect the migration projects i.e. customer can easily migrate from older version to new one without worrying about this new feature