It looks like if you did *not* file your 2018 tax return, you *cannot* EFILE using the Stimulus edition of Turbotax.
It looks like the IRS identifies one by their prior year AGI or their self-selected pin number (from prior year). Since 2019 filers will not have information from 2018 (e.g. AGI or PIN), they cannot efile using the Stimulus edition since it does not offer a place to enter the AGI (e.g. zero).
Let me know if anyone finds a work-around other than to use the following IRS link:
https://www.irs.gov/coronavirus/non-filers-enter-payment-info-here
