It was definitely not professional (or trust building) for the director to make that promise to you and then break it. If he could not guarantee you that you would be allowed to continue with your previous T, he should have said so up front.

It also seems irresponsible for them not to allow you a termination session, even if it meant the director or your new CBT therapist overseeing that termination session.

The director and/or your new T should also be open with you and disclose the reason for requiring that you terminate with your old T. They can't expect you to understand if they don't explain it to you!