You want to know if you can use TrustFile to file late or delinquent taxes by having a return amended or backfiled.
TrustFile is only available to file current period's returns and will not file late or delinquent returns. We do not offer the service of amending returns or backfiling previous month's returns with TrustFile.
In addition to state due dates there are filing deadlines within TrustFile that if missed the filing responsibility falls on you to file directly with the state. For further information on what those filings deadlines are you can check the States Guides for TrustFile.
If you need to file delinquent taxes you will need to work directly with the state to arrange that filing.