In reply to Glyn Davies:
Hi there, I'm sorry about the communication failure - your webforms should be coming to me, but they haven't. I've asked our web developer to look into it.
Unfortunately you have indeed paid for information twice. This is one of the problems we have with using Apple's hosting.
If you'd bought North Wales Climbs first, you would have been warned you were about to pay for something unnecessarily when you tried to buy Slate Quarries by some custom code I've added, but buying a subsection, then deciding to buy the whole thing is something people do on purpose, so there is no warning. Ideally the price of North Wales Climbs would have been reduced by the amount you'd already paid, à la iTunes "complete my album", but this functionality is not exposed to third parties by Apple.
The other confusing thing about this particular situation is the price of the slate package is similar to (or the same as?!) the whole NWC package. That is something to do with the recent release of the Slate guidebook, so the slate package is now vastly bigger than it was originally.
You may still be able to get a refund from Apple - I see my list at reportaproblem.apple.com includes an in app purchase from more than 14 days ago. Failing that, I suggest you try and get in touch with a human at Apple to get a refund. It may be worth telling them to speak to me if they want confirmation of the chain of events that led to you not getting the refund in time: stephen@rockfax.com