Tomb Raider, I went to BA’s website. I typed in the departure and the destination and it came up with the rest. You can also select the class of seat. Wtp being one.
At no time did I say that BA offered this class. I was demonstrating the point, that if you want more you pay more.
You will also notice that I used the word THEORY at the beginning of the example.
Yesterday when I did this research, the site gave the figures posted. However today, the same site is now telling me that WTP is not available (as you have stated) on this route. The site will now only quote first class at around £11500. It would appear tweaking to this site is still ongoing.