Howard - as I don't have a lot of stock of the CDs they're holding I'm very reluctant to destroy them. And yes, it would be writing off their own value and the postage I've already paid out to send them. I'd far rather not do that, but then I don't want to be in this situation anyway. They're not offering me the solution of sending them to Amazon.
I have no issue at all with queueing at our very friendly and helpful post office, but I do have a problem with the cost of the postage. Which I can factor in when I'm selling via Bandcamp or my own website, but can't adjust for in the price I receive from CDBaby - and my arrangements with CDBaby were made before the postage costs went shooting up. Also before CDBaby decided not to sell directly to purchasers and thereby reduce the amount I can receive per sale. It used to be a good solution, to sell to US customers via CDBaby, once upon a time.
I'm happy in future to work with Bandcamp and direct sales from my website - this is a short-term issue and will be resolved by the end of November. But it is very frustrating.