I feel your pain, BillB, although my time investment of about 4 hours solving this issue may not have been as much as you experienced. I contacted Apple after reading this post. After a few questions to understand problem they asked if I had tried saving to desktop, I had not. After saving tax file to desktop the issue went away. I had to renter some data but not too much effort. I was just glad to have a working path forward.
I am also a long time Mac and TurboTax user and have never had this issue before. As you said, a software code expert should be able to resolve this issue and improve the customer experience. I do hope this issue gets resolved.
