I had a strange occurrence on the FTC website where it kept changing the passenger numbers I entered. I read the FAQ (no help) and it told me that I could do one of two things:
1. Ring the customer service number (20p per minute)
or
2. Fill in the Question form
So I filled in the question form. When submitted, they thanked me for my enquiry and said they aim to reply within 4 DAYS!
In fairness, they did, within 4 days.
Answer: Ring the customer service number (20p per minute).
You couldn't make it up.