I have been studying A2-B1-B2-TestDaF and every time the group was different.
The DaF test is what you need to become a student in Germany. It has really high expectations, not only in term of language comprehension but also in terms of mind flexibility and agility.
You need for example to argue a position or to convince a friend of something with a preparation time between 1min30 and 3 minutes.
We often complained by saying that even a fluent german speaker could fail at that test.
Here is the group, I let you find the teacher :)