My delving deeper involves contacting Protopage, they have responded quickly saying :-

"You're not doing anything wrong, but Flyertalk are denying access from our indexing server. We've just emailed them to ask them to unblock us. Hopefully they will respond."


I realise this is an easy thing for them to say and I have no idea what an indexing server is nor the implications of denying access but hopefully whoever in Flyertalk will get that email will either resolve it or respond with further information.

Thanks