Newly issued forms do not go instantly from the IRS web site into TurboTax. The TurboTax development team has to program the new form, test it, and get IRS approval before they can incorporate it in the TurboTax software. The current estimated date for Form 8915-B to be available in 2019 TurboTax is May 14, 2020. That data is subject to change. You can check the expected availability of forms in TurboTax at the following link.
IRS forms availability table for TurboTax individual (personal) tax products
