Whenever I travelled far for a punt (which is nowhere near 330 miles.... The furthest I've travelled for a punt is probably near 200 miles), I always picked the girl with good feedback, and then made an advance booking a few days before (or 3 weeks in advance with one particular escort). On the whole, those punts turned out quite well.
There was one occasion where I did book an escort in Norwich on the very day (this was only because a meet I booked in advance in Bristol was cancelled) because I wanted to punt. Norwich is over 100 miles from Leicester. I went there and it was a disaster (Plan B punts are generally underwhelming for me anyway).