I usually only do 1 hour for any student GCSE or under, as they struggle to concentrate for longer, and some even for that time.
I take the approach that tutoring is different from learning in school, and the primary focus is to get the student to take control of their own learning, identify gaps and weaknesses in their knowledge, and motivate themselves to learn. As a tutor, my job is to find out (from them) what they don't know, why, and how they learn best, and teach them strategies for learning using the examples of what they struggled with this week.
The aim is to get the student to the stage where they can self-identify a weakness, seek specific information and strategies from me, then use them to explain back to me the material they didn't understand at the start. This means that early tutorials with a student will cover "less content" than later ones, and that building a rapport with the student is essential. It also means it's more like a conversation than a lecture. I tend to draw a lot in tutorials and show them different approaches. Approaching an exam, or for a few short sessions, I might look at exam questions, including strategies for answering them, model answers, and comparing approaches, but this would not be core to ongoing tuition until the exams were approaching.
I think what this shows from the posters so far is that different tutors have very different styles, and you want to find the one who fits with your child.