Comment 2 for bug 1770370

We do have some plans to renovate the way we've modeled user (for example, to use a primary key instead of username as an internal identifier).

However, it will not cover re-using usernames. Usernames must be unique for several reasons - non-repudiation and audit being some of them. Reinventing and inventing unique usernames are standard practice everywhere: if you have 2 employees that want the same username, they are generally forced to append a number or some similar tactic.

So given that:
1. we will not physically delete a user from our database (only logical deletes take place);
2. you as an operator want to re-use usernames from 'logically deleted' users;
3. we will be using user's primary key to link Juju components such as user permissions on models, etc...

then we can allow you to re-user a username as long as all other occurrences of this username are associated with 'logically deleted' users.