I had a standard reply to my complaint to Amazon. Probably worded in the way it was because I went through Marketplace (being the only place I could find an email form)
I'm sorry about any misunderstandings regarding the listing of this item. In researching ASINs 0762435739 and 0762436581, I see these items are listed with a release date of April 13. Because Amazon Marketplace sellers are not able to list items for pre-order on our web site, the item is currently ineligible for Amazon Marketplace selling. You may have seen the Sell Yours Here button earlier, before the publisher made any changes to the release date.
After April 13 has passed, you should be able to list these items. Please try to create your listings again after the release date.
I hope that this information was helpful.
Of course I pointed out that it wasn’t at all helpful, had nothing to do with Marketplace, and that I didn’t wish to list these items. (you doofuses, I muttered under my breath) but at least now we have a dialogue and a “contact complaint number” – so I’ll keep pushing and see what they say.