"because they said the deadline is 10/19."
No, "they" did not. Please do not state things that are not true. You are mixing up two functions that are not related, just because you see the word "conversion."
The File Conversion for moving specific data across years and programs has nothing to do with efiling.
Conversion as part of the e-filing Transmission Process is not the same thing as File Conversion for purposes of which Program you use to prepare tax returns.
"Intuit will be performing annual maintenance on the Data Conversion Service in preparation for Tax Year 2020 beginning Oct 19. During this time Tax Data Conversion will be unavailable. Oct 18 is the final date to submit tax data for conversion in ProSeries 2019. After this time, 2018 tax files will no longer be processed, and conversion services will resume when we begin accepting 2019 tax files with the release of 2020 ProSeries. Note: This information does not impact or relate to electronic filing."
It's not semantics. It's Function. It's for Moving client data files between Programs; not Filing with the IRS Fed or State return processing.
"Level Up" is a gaming function, not a real life function.