TT is allowing users who started the online return to continue to finish and efile until 10/29 this year ... it will be considered "late filing" but it is being allowed. Professional tax programs can continue to efile 2018, 2019 & 2020 returns until sometime late November. After that the IRS closes efiling completely until sometime in January for the switch to the next tax year.
https://ttlc.intuit.com/community/filing-and-paying-taxes/help/what-if-i-missed-the-october-15-filin...
