PlusGuidance follows standard professional practice for structured therapy sessions and sets the session length time at 50 minutes. Shorter sessions often do not allow enough time to go into detail about issues or discussions, and it turns out that 50 minutes seems to work best for both parties.
Being 10 minutes less than a full hour has the added benefit of leaving some flexible time for situations where either party turns up late, has to restart their internet connection or their device, etc.
It should be noted that the first session you can book for free with any therapist, before you subscribe to a plan, is set to 15 minutes. This is because this first free session is meant to just be an introduction where you can see if you feel comfortable with the therapist, ask any questions you have about the therapy process, etc. It's more a consultation and less like a therapy session, because it's limited how much you can dig into things in that short time.