Problem adding a new user?

Last month I added 18 users to my Cap Prime account. I used a CSV file that included the learner manager's email account to identify the supervisor. No problem even though the senior most manager was NOT listed as a Captivate user, only his email account was added as the supervisor of a manager.

Today, (after the Feb 2016 release of Prime) I can't add a new user because the person's manager isn't already in the system.

However, my original CSV file listed the same manager (using his email account) as the supervisor of a manager over everyone else on the CSV file.

So what has changed? And what do we do when we want to add someone who doesn't have a supervisor? Like the CEO of the company? At some point, we have to have the ability to add someone who doesn't have a supervisor.

Am I missing something obvious?