Hey sootchucker were you able to get that data?
You'll find the adaptation channels labels and factory set temperature values on previous page, post #15, thanks to jivemonkey. I can confirm that they are the same on my GTI, however I have changed the temperatures a bit for the first and second settings.
Seat heating stage 1 lower switching threshold 28.50 °C
Seat heating Level 1 Upper threshold 29.50 °C
Seat heating stage 2 lower switching threshold 28.50 °C
Seat heating Level 2 Upper threshold 29.50 °C
Seat heating stage 3 lower switching threshold 39.00 °C
Seat heating Level 3 Upper threshold 40.00 °C
Seat heating stage 4 lower switching threshold 39.00 °C
Seat heating Level 4 Upper threshold 40.00 °C
Seat heating stage 5 lower switching threshold 52.50 °C
Seat heating Level 5 Upper threshold 53.50 °C
Seat heating stage 6 lower switching threshold 52.50 °C
Seat heating Level 6 Upper threshold 53.50 °C