Buy BP Ultimate.
Expensive I know, but they have a dedicated helpline, at least for people who put petrol in a diesel. I did!
The livery is so similar in design and colour, and both diesel and petrol pumps say "Ultimate", that this happens all the time apparently. The filling station bloke knew exactly what to do as, he said, he gets lot of these in a month.....
BP will, providing you have the receipts, pay all costs, except for new fuel. This includes a new engine and all the ancillary expenses should you blow up on a motorway
.
A very pleasant woman deals with it and I was much impressed. But not really, if you know what I mean!!!
My own dealer was also very, very helpful by the way.
Yes, I was silly, but I was tired, it was poor light, and I had no idea that there was petrol Ultimate as I had only seen the add for diesel.
Needless to say, I stick with my local Shell station now