In the end I did contact them again, saying that they made no attempt to tell me that these eBooks would no longer be available, and consequently no chance to back them up before they were removed. It seems that when pushed hard enough they will give way.
Thank you for your reply. This issue has been reviewed and here's what we will do. According to the catalog, we no longer have the following books in any format: Star Trek: TNG: Q & A, Star Trek: TNG: The Sky's the Limit: Book 1, and Star Trek: TNG: The Insolence of Office, therefore I have credited your account with the purchase price of these books in Rewards Dollars, which can be used on future purchases.
We do have ePub versions of Star Trek: Enterprise: Kobayashi Maru and Star Trek: Destiny #3: Lost Souls, so I have exchanged those books to that format. You can download these at any time from your Bookshelf using Adobe Digital Editions as normal. I've also exchanged the distributor for I, Claudius and tested it to make sure it works, so you should be able to download that one now as well.
I apologize for any inconvenience caused by Amazon discontinuing the Mobipocket format. Please let me know if you have any other questions and I will be happy to assist.
If I left some of my physical books in storage and they were removed by the owner of the storage without my notice or permission would that be not classed as stealing? Why should digital property be seen as any different and don’t get me started on DRM.