In 3 to 4 weeks, when IRS opens the gates and ProSeries flicks the switch because the software is good to go.
Here's wishing you many Happy Returns
You'll be able to do that when the IRS re-opens the MeF system.
"We" don't know that date, and the IRS hasn't yet announced it.
You can sign up for Alerts at irs.gov so that you will know as soon as the rest of us do.