Thank you Mark - it is the same. The dealers set it, so I suppose it is for street use. I don't race her anyway. That's how I got more than 26,000 kms out of the first set of tyres.
The Nissan dealer told me that the tracking should be checked every year. I don't think it was the first year, but I am not sure. I think the tracking went off when I drove up the Pyrenees in the summer at a little more than a leisurely pace. Pulling 1.5g for a period of time does it, I think, but one only lives once. I had a bit of extra wear on the inside of the tyres, but the front only had a couple of thousand kms left in them, probably 4k on the rear, but all the tyres need changing at the same time, so there it is.
Thanks for taking the time to help.