Problem Solved, Finally.
1. The latest Arizona update occurred on 3/4/21 - I applied that.
2. I also removed the entire State Tax Return using this process:
https://ttlc.intuit.com/community/state-taxes/help/how-do-i-clear-my-state-return-in-the-turbotax-fo...
3. Saved and then Saved As a new version.
When doing Arizona State return, TurboTax still caused the same error of requiring the completion of MSP even though we are a single state provider of services.
4. Switch to Manual Forms (upper right) when the MSP form error reappeared and had to delete it manually.
However, unlike previous attempts this time no additional errors were caused or repeated and the state and federal reviews completed successfully.
