Is this not telling you in advance?

As far as I'm concerned it is entirely up to the therapist the terms of their care. Now, they would owe you an explanation. Perhaps they think they have done all they can for you. Perhaps there is a question over the nature of the direction therapy has been taking. Is there transference - that would definitely be a reason to end a professional working relationship.

Now, if this therapist felt you still required therapy I feel they ought to be responsible for making a referral to different care provider.