Can I change tenancy name or create new tenancy on free tier

Summary:

Hello. I created an account with a temporary / placeholder tenancy name.

When creating the account, the Oracle sign up page was clear the tenancy name can be changed. However, I have looked at various resource and it seems tenancy name cannot be changed - see in particular:

https://community.oracle.com/customerconnect/discussion/651425/not-having-permissions-on-my-tenancy-after-tenancy-name-has-been-changed

Can someone please advise:

1) Can the tenancy name be changed on free tier account?

2) If no - is it possible to create a new tenancy, then delete the original, while staying on free tier?

3) Otherwise - can tenancy name be changed on a paid account, and is it possible to later move back to a free account at later date?