It is part of the way my therapist works that he is willing to be available for coaching calls outside of office hours. It's probably one of the most helpful aspects of my therapy. There is nothing unprofessional about these calls - it's explicitly part of the therapy.

Being about to reach out at an early stage of a depressive episode has helped me stop from relapsing or falling deeper into crisis.

I suspect when people have problems with relationship difficulties with their therapists, these difficulties would happen with or without outside contact. And several times, in the beginning of our work together, being able to contact him for clarification helped avert trouble that was brewing due to misunderstanding each other in session.

In contrast, I remember having very difficult times with my first therapist as it simply hadn't occurred to me that I could ever contact him between sessions - we had a few misunderstandings that led to deeper problems thanks to my tendency to ruminate. Not being able to clear the air for a week or two caused me a lot of emotional anguish.