Since then I asked them about these "hand signals" and they work as follows:
- hand dropped to the right = obstruction coming up on the right
- hand dropped to the left = obstruction coming up on the left
- both hands dropped = obstruction across the whole road
- hands raised above the head = obstruction from above, i.e. hanging branches
Looking forward to the cross country on Saturday, will be a good test to see how I have improved in the last three weeks (since the last cross country).