This is what the IRS is saying about it:
"Because Form 8915-E is new and impacted by recent legislation, it has not been enabled in XML for e-filing, and e-filed returns are to include an attached PDF of Form 8915-E."
To my knowledge, TurboTax has never supported the inclusion of an attached PDF. I'm thinking we'll have to use a paid tax preparer with professional software, if TurboTax can't figure this out quickly. Alternatively you could mail your return but then you won't get a refund for months. The IRS hasn't even finished processing the 2019 paper returns.
If you're trying to get your 2020 return filed fast so that you can qualify for the upcoming March/April Biden stimulus, I would go to a professional.
Here's the IRS link:
https://www.irs.gov/forms-pubs/alternative-filing-method-for-e-filed-returns-that-include-form-8915-...
