I have mentioned what I thought was a very strange tiny oil leak previously on here. Basically I found a couple of drops of oil sitting on the rocker cover but couldn't be sure where it was coming from.
Well during a 1000 mile trip to France and back, I got no oil leak at all. Then today, I went out for a drive, and I was pushing it quite a bit for a while (foot down high revs etc). Got back, and found oil again, but this time definitely coming from the oil cap.
I realise it could just be a duff oil cap...but when I search the internet I see all sorts of horrible other reasons, such as positive crankcase pressure. As the car is new, I can't see that the breather pipe could possibly be blocked!