Audi Avant A6 Avant - 08 - Tyre Pressure and such

Changed the vehicle and now towing with an Audi A6 Avant (estate) on an 08 Plate, are there any known issues or anything i need to know re the relationship between the Audi and my van.

I've checked via the 'Outfit Check' and the Audi passes all of the checks (along with the van) with no problems

Do I need to push up the tyre pressure when towing on both the rear and the front or is it just the rear?

By How Much?  is there a std amount, I seem to remember adding around 5lb pressure with my previous vehicle?

At the moment I cannot find the tyre pressure for the car on the car or the manual...don't know why and I do not have the addon via the onscreen display to check tryre pressures so it's down to me.

Any further advice would be much appreicated.