is the only remedy (without filing an amended return) the method you describe and start the depreciation clock over again in 2022, beginning with the new cost basis?
It's not the only remedy. But it's the best remedy that is the simplest without you amending either the 2020 or the 2021 tax return. You will need the landscape printouts of both 4562's for that rental property from your 2020 tax return, in order to "do the math" to get the correct new cost basis for the 2022 return. You'll also have to keep track of that prior depreciation yourself, outside of TurboTax, since you will be required to recapture it when/if you sell the property in the future.
If you're going to amend, I would suggest you amend the 2021 tax return. But if you do that, then you can't even start your 2022 tax return until you complete the amended return. That's the only way to ensure the correct (amended) values from 2021 are imported into the 2022 tax return, and assuming the property remains "in service" for the entire 2021 tax year, even if it did sit empty because of COVID. (That happened to a lot of landlords that year. So it's not a red flag or anything.)
