They are playing a set on the Brighton Naturist beach
and claim to be naturists themselves (they are also doing another naturist centre gig as well), so I am assuming that 90% of the people at that stage of the ride will be fully nude, so will they.
The great British weather may have some factor in this, I am keeping my fingers crossed as we have had 4 rides in sunshine so far, and it seems to be too good to expect another one! Here's hoping!